M4 Motorway
Road of the United Kingdom
Length	189. The United Kingdom Road Network is an extensive network of routes connecting its settlements The network is of varied quality and capacity The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located 5 miles (305 km)
Direction	East - West
Start	Chiswick
Primary destinations	Hounslow Heathrow Airport Slough Maidenhead Reading Newbury Swindon Chippenham Bristol Newport Cardiff Bridgend Port Talbot Neath Swansea Llanelli
End	Pont Abraham services
Construction dates	1961 - 1996
Motorways joined	4B - M25 motorway 8/9 - A308(M) motorway 8/9 - A404(M) motorway 10 - A329(M) motorway 19 - M32 motorway 20 - M5 motorway 21 - M48 motorway 22 - M49 motorway 23 - M48 motorway 29 - A48(M) motorway
Euroroute(s)	E 30
Opening timeline

The M4 motorway is a motorway in Great Britain linking London with Wales. Chiswick ( IPA /ˈtʃɪzɪk/ is an area of West London, located west of Charing Cross, which covers the eastern part of the London Borough of Hounslow The United Kingdom Road Network is an extensive network of routes connecting its settlements The network is of varied quality and capacity Hounslow is the principal town in the London Borough of Hounslow. Slough ( ˈslaʊ is a Borough and Unitary authority within the ceremonial county of Berkshire, England. Maidenhead is a town within the Royal Borough of Windsor and Maidenhead, in Berkshire, England. Reading (ˈrɛdɪŋ as Redding) is a town in England, located at the confluence of the River Thames and River Kennet, midway between Newbury is a Civil parish and the principal Town in the west of the County of Berkshire in England. Swindon ( is a large town in the ceremonial county of Wiltshire in the South West of England, midway between Bristol (64 km / 40 miles Chippenham is a Market town in Wiltshire, England, located at, some 21 km (13 miles east of Bath and 163 km (96 miles west of London Bristol ( ˈbrɪstəl is a city, Unitary authority and ceremonial county in South West England, west of London Newport (Casnewydd is a city and principal area in Wales, in the United Kingdom. Cardiff ( 'kɑːdɪf) is the Capital and the largest city and county in Wales. Bridgend (Pen-y-bont ar Ogwr is a town in the Country Borough of Bridgend in Wales. Port Talbot ( Welsh: Aberafan or Porth Talbot) is an Industrial Town in south Wales, UK, with a Population Neath (Castell-nedd is a Town and community situated in the principal area of Neath Port Talbot, Wales, UK with a Swansea ( Abertawe "mouth of the Tawe " is a city and county in Wales. Llanelli ( English: Church of St Elli) pron, the largest Town in the County of Carmarthenshire, in south-west Pont Abraham services is a Motorway service station on the M4 motorway in Wales. Year 1961 ( MCMLXI) was a Common year starting on Sunday (link will display full calendar of the Gregorian calendar. Year 1996 ( MCMXCVI) was a Leap year starting on Monday (link will display full 1996 Gregorian calendar) To see information about the M25 motorway under construction in Ireland, see N25 road. The A308(M is a Motorway in Berkshire, England. It is 06 Miles (1 Km) long and is possibly England's shortest motorway, although The A404(M is a Motorway in Berkshire, England and can be referred to as the Maidenhead West Bypass. The A329(M is a Motorway in Berkshire, England. It is 4 Miles (6 The M32 is a Motorway in South Gloucestershire and Bristol, England. This article is about the M5 motorway in England See M5 for other roads numbered "M5" The M48 is a Motorway in Great Britain joining Gloucestershire and Monmouthshire over the original Severn Bridge. The M49 motorway is a small Motorway west of Bristol, England, that forms a shortcut between the M5 motorway and the Second Severn The M48 is a Motorway in Great Britain joining Gloucestershire and Monmouthshire over the original Severn Bridge. The A48(M is a Motorway in Wales between Cardiff and Newport. The international E-road network is a numbering system for Roads in Europe developed by the United Nations Economic Commission for Europe (UNECE. European route E30 is an A-Class West - East European route, extending from the southern Irish port of Cork in the west to the Motorway is a term for both a type of Road and a classification or designation See also Kingdom of Great Britain Great Britain (Breatainn Mhòr Prydain Fawr Breten Veur Graet Breetain is the larger of the two main islands London ( ˈlʌndən is the capital and largest urban area in the United Kingdom. It is part of the unsigned European route E30. European route E30 is an A-Class West - East European route, extending from the southern Irish port of Cork in the west to the Other major places directly accessible from M4 junctions are Reading, Swindon, Bristol, Newport, Cardiff and Swansea. Reading (ˈrɛdɪŋ as Redding) is a town in England, located at the confluence of the River Thames and River Kennet, midway between Swindon ( is a large town in the ceremonial county of Wiltshire in the South West of England, midway between Bristol (64 km / 40 miles Bristol ( ˈbrɪstəl is a city, Unitary authority and ceremonial county in South West England, west of London Newport (Casnewydd is a city and principal area in Wales, in the United Kingdom. Cardiff ( 'kɑːdɪf) is the Capital and the largest city and county in Wales. Swansea ( Abertawe "mouth of the Tawe " is a city and county in Wales.

The M4 runs close to the A4 from London to Bristol. After crossing the River Severn it follows the A48 through Wales, until its termination just north of Pontarddulais. For other rivers named "Severn" see Severn River. The River Severn ( Welsh: Afon Hafren, Latin The A48 is a major Trunk road in Great Britain. It runs from the A40 at Highnam west of Gloucester to the A40 at Carmarthen Pontarddulais ( is a Town in the City and County of Swansea, Wales, known by locals as "The Bont"

Special features

In London, the eastbound (London-bound) M4 carriageway has a bus lane from junction 3 until the elevated section. A bus lane or bus only lane is a lane on a road restricted to Buses and generally used to speed up public transport otherwise held up by traffic congestions This lane caused some controversy when it was created. ^[1] However, the bus lane has improved traffic flow onto the 2-lane elevated section which follows it. There is some speculation that the original plan involved closing one lane from junction 3 to the elevated section to prevent congestion caused by the filtering of three lanes of traffic into two (the motorway is already temporarily down to two lanes at junction 3 because the left lane is exclusively for traffic leaving the motorway, so the effect of the bus lane is to make the 3-to-2 lane-transition seamless). Making the "spare" lane available for buses - and now taxis and motorcycles - was an afterthought. ^[2]

The M4 near Bristol (England) between junctions 19 and 20, looking west towards Wales. Bristol ( ˈbrɪstəl is a city, Unitary authority and ceremonial county in South West England, west of London England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland

The elevated section in West London, built in the 1960s, is mostly directly above the A4 and extends over parts of Brentford's Golden Mile. Brentford is a suburb in the London Borough of Hounslow at the Confluence of the River Thames and the River Brent in West London The Golden Mile is the name given to a stretch of the Great West Road north of Brentford running west from the western boundary of Chiswick in London This section has a heated road surface to reduce icing in winter.

The motorway is the only one in the UK to feature a 'dual-numbered' junction. Junction '8/9' is the turn off for Maidenhead, Berkshire. Maidenhead is a town within the Royal Borough of Windsor and Maidenhead, in Berkshire, England. Berkshire (ˈbɑːkʃə or /ˈbɑːkʃɪə/ say Baak-shuh/-sheer sometimes abbreviated to Berks) is a Home County in the South

There is a special slip road west of the A34 to Newbury from the eastbound carriageway which leads to RAF Welford. The A34 is a major road in England. It runs from the A6042 in Salford to Winchester in Hampshire. Newbury is a Civil parish and the principal Town in the west of the County of Berkshire in England. RAF Welford is a UK Royal Air Force station which is presently utilized by the United States Air Force. This slip road is signposted in red lettering (the normal military signing standard), "Works Unit Only".

It has two of only three four-level stack interchanges in the UK, including the first UK example at the junction with the M5 (J20/"Almondsbury Interchange") and the other at the junction with the M25 (J4B). A stack interchange is a free-flowing junction between two or more roads that allows turning in all directions The Almondsbury Interchange in South Gloucestershire, is one of the United Kingdom 's largest motorway Stack interchanges The interchange is one of only Both are impressive feats of engineering, particularly junction 4B which also has to make provision for a railway line passing beneath the M4. However, due to the nature of such junctions, drivers should bear in mind that it is impossible to make a U-turn at J20 or J4B.

The M4 crosses the River Severn via a toll bridge, the second of only two on the UK motorway network – the first was the original Severn Bridge (the original route of the M4, now the M48). The Second Severn Crossing ( Welsh: Ail Groesfan Hafren) is a Motorway crossing over the River Severn between England and Wales For other rivers named "Severn" see Severn River. The River Severn ( Welsh: Afon Hafren, Latin A toll bridge is a Bridge over which Traffic may pass upon payment of a fee or toll. For the Ontario community see Severn Bridge Ontario Not to be confused with Second Severn Crossing The The M48 is a Motorway in Great Britain joining Gloucestershire and Monmouthshire over the original Severn Bridge.

The M4 passes through the Brynglas Tunnels at Junction 25a, Newport. The Brynglas Tunnels carry the M4 motorway under Brynglas Hill in Newport. Newport (Casnewydd is a city and principal area in Wales, in the United Kingdom.

Near Junction 35, there is a stretch of the motorway that has a surfacing of porous asphalt that improves drainage and reduces noise. Asphalt concrete, normally known simply as Asphalt, is a Composite material commonly used for construction of pavement, Highways and When driving in heavy rain conditions drivers notice a reduction in spray from other vehicles and improved visibility. This special surface was publicised in an episode of the BBCs Tomorrow's World programme. This was the site of the first trial of the new road surface when it was laid down in 1993^[3].

Notable junctions

Junction 27 at High Cross is a normal roundabout B-road junction, however the slip roads point in the wrong direction to the destination. Due to the topology of the landscape, both sets of sliproads are conjoined on opposite sides of the roundabout. To go to Cardiff, the driver must use an eastbound-facing sliproad before looping around 180 degrees to join the westbound carriageway.

During the construction of the section around Cardiff in 1980, junction numbers were set aside for intermediate interchanges that were not built at the time. Cardiff ( 'kɑːdɪf) is the Capital and the largest city and county in Wales. 33 had been set for the link road to the west (A4232), 32 for the A470, with 31 intended for the A469 to Caerphilly, and 30 for the great "Hook Road" - a plan which was later shelved. The A4232, which is known either as the Peripheral Distributor Road (PDR (Ffordd Ddosbarthu Ymylol or the Cardiff Link Road (Ffordd Gyswllt Caerdydd is a The A470 is a major long-distance connective spine road in Wales, running from Cardiff on the south coast to Llandudno on the north coast Caerphilly (Caerffili is a town in the County borough of Caerphilly, south Wales, located at the bottom of the Rhymney Valley, with Junction 30 was later added to serve the A4232 link road, in the east, which will eventually form a ring road from junctions 33 to 30, via Cardiff Bay. The A4232, which is known either as the Peripheral Distributor Road (PDR (Ffordd Ddosbarthu Ymylol or the Cardiff Link Road (Ffordd Gyswllt Caerdydd is a Cardiff Bay (Bae Caerdydd is the area created by the Cardiff Barrage in South Cardiff, Wales. Number 31 remains unused as of 2006, and there are no immediate plans to build a junction with the A469.

The original bridge over River Neath (the A48), is to the right, the new M4 bridge is to the left

Contrary to popular belief, junction 39 does exist. However, it consists of a single slip road completing the missing movement onto the westbound carriageway from the A48 at junction 38, thus there is no exit from the motorway at this junction. The A48 is a major Trunk road in Great Britain. It runs from the A40 at Highnam west of Gloucester to the A40 at Carmarthen

Junction 41 refers to two different junctions in two different directions, their movements not complementary. In the westbound direction, 41 is indicated as a spur leading to the roundabout in Briton Ferry formerly known as 41A, and the original bridge over the River Neath, which would allow access onto the stretch of the M4 from junction 43 westward. Briton Ferry (Llansawel is a Town and community in the County borough of Neath Port Talbot, Wales. River Neath ( Welsh: Afon Nedd) is a river in south Wales running south west from its source to its Confluence with Swansea Bay below In the eastbound direction, 41 is indicated as an exit-only route to the A48 towards Port Talbot. As a result, it is possible in both directions to travel almost 2 miles (3 km) in the same direction having both joined and subsequently left the motorway at "junction 41".

Speed checks

Speed checks are carried out between junction 14 and junction 18 (in both directions). These are carried out by police camera vans situated on bridges over the motorway. See also Traffic enforcement camera A mobile speed camera is a term used in the United Kingdom to refer to a Road vehicle fitted with Speed These measure the speed of vehicles using laser detection equipment. The introduction of these measures proved controversial and resulted in a public protest, involving a go-slow of several hundred vehicles along the affected sections of the motorway during April 2005. ^[4]

Traffic heading into London travels at a maximum speed of 60 mph (97 km/h) after the Heathrow turnoff, the limit is enforced by cameras. A traffic enforcement camera is a system including a Camera and a Vehicle -monitoring device used to detect and identify vehicles disobeying a Speed limit The elevated section is also enforced by speed cameras at 40 mph (64 km/h). Traffic heading out of London is limited to 40 mph (64 km/h) on the elevated section, but there are no cameras.

The M4 between junctions 22 and 23, crossing the River Severn from England to Wales on a cable-stayed bridge (the Second Severn Crossing). For other rivers named "Severn" see Severn River. The River Severn ( Welsh: Afon Hafren, Latin England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland A The Second Severn Crossing ( Welsh: Ail Groesfan Hafren) is a Motorway crossing over the River Severn between England and Wales Wales is seen in the distance.

Speed checks are also carried out by mobile Safety Camera Partnership vans on the toll plaza on the Welsh side of the M4 after the Second Severn Bridge. See also Traffic enforcement camera Safety Camera Partnerships (SCP were Local Government -based organisations set up in the United Kingdom as part The speed limit is reduced to 50 mph (80 km/h) when approaching the toll plaza, the theory behind this is to protect tolling staff moving between the tolling booths^[5], the limit is then raised back to the National speed limit after leaving the toll plaza. The United Kingdom Road Network is an extensive network of routes connecting its settlements The network is of varied quality and capacity There are also mobile camera vans on sections of the M4 between the toll plaza and Cardiff.

Between Junction 34 and Junction 37, there are three bridges crossing over the motorway. These three bridges sometimes have mobile speed camera vans parked on them to catch speeding motorists on the motorway below. These bridges are located on fairly sharp bends in the motorway.

The section between junction 40 and junction 41 has a maximum speed of 50 mph (80 km/h), and is enforced by a permanent speed camera (Gatso), to be found near junction 41 in the eastbound direction. See also Traffic enforcement camera Gatso is a Brand of Speed camera invented by Maurice Gatsonides and manufactured by the Dutch To improve traffic flow, the westbound speed camera was removed in late 2006 and replaced with an electronic warning sign. ^[6]

Temporary average speed cameras are in operation around Junction 6 at a speed limit of 50 mph; operation commenced westbound on Monday 26 November 2007 while roadworks on the bridge are taking place (expected to last 40 weeks according to signs alongside the carriageway). Eastbound average speed cameras in the same location were operational a short time after that.

Between Junction 29 and Junction 32, there are 2 speed cameras on the westbound carriageway, one just before Junction 30 (it is clearly visible against the junction exit sign), and another under a bridge approximately 1 mile before Junction 32. On the eastbound carriageway, there are 2 cameras, one approximately 1. 5 miles after Junction 32 and the other is approximately 1 mile before Junction 30.

Developments

M4 widening between junctions 29 and 32. The eastbound carriageway (right) is nearing completion. The westbound carriageway due to begin in 2008

As of spring 2007, the stretch between Junction 29 Castleton and J32 Coryton is being widened to 6 lanes in order to relieve congestion that plagues this stretch. Work is expected to be completed by December 2009^[7].

Junction 11, near Reading, will be extensively developed commencing in Spring 2008 and lasting until well into 2010 in an attempt to relieve congestion. Reading (ˈrɛdɪŋ as Redding) is a town in England, located at the confluence of the River Thames and River Kennet, midway between The development will not only build two extra bridges, and re-route many roads by the junction, but will also involve the movement of the local Highways Agency and Fire Service offices, build a long footbridge network, a special bus-lane and a new gyratory. The Highways Agency is an Executive agency, part of the Department for Transport in the United Kingdom. The fire service in the United Kingdom operates under separate legislative and administrative arrangements in England, Northern Ireland, Scotland and A bus lane or bus only lane is a lane on a road restricted to Buses and generally used to speed up public transport otherwise held up by traffic congestions A roundabout is a type of Road junction at which Traffic enters a one-way stream around a central island Redevelopment of roundabouts on the A33 and the installation of a new junction off that road will be part of the works. It will also install sound barriers for nearby residential areas, some of which have already been completed. ^[8] In April 2008, the decision to preserve a rare Vickers Machine-gun Pillbox and turn it into a bat roost was announced by the developers. The Vickers machine gun or Vickers gun is a name primarily used to refer to the water-cooled. ^[9]

There have been calls to close the slip roads at Junction 40 and 41 (at Port Talbot) to improve traffic flow in the area. The motorway is only two lanes in this stretch and this stretch is a major traffic congestion blackspot. Junctions 40 and 41 (at Port Talbot) have very short slip roads which are not up to modern standards. ^[10]

The "missing" Junction 31, also known as the Thornhill interchange, which was originally granted planning permission in September 1991 (but subsequently expired)^[11] have been rekindled after plans for a new business park on a 125 acres (1 km²) site north of the M4 were submitted to Cardiff Council. Thornhill ( Welsh Draenen Pen-y-Graig draen thorn + -en one + pen top + craig rock is a Suburb In the field of Road transport, an interchange is a road junction that typically Political makeup Elections take place every four years The last election was 1 May 2008. The developers of the business park, St Modwen Developments, would likely fund the new junction, which would be on the A469^[12]. The A469 is a road in South Wales. It links Cardiff and Caerphilly with Rhymney and the Heads of the Valleys Road (A465.

New M4

Main article: New M4

Plans are progressing for the New M4 Newport bypass. A New M4 (sometimes known as M4 Toll Motorway) has been proposed for the south of Newport, South Wales, and could be the United Kingdom 's second A New M4 (sometimes known as M4 Toll Motorway) has been proposed for the south of Newport, South Wales, and could be the United Kingdom 's second The Welsh Assembly Government Transport Minister Ieuan Wyn Jones said "We could start the work in 2010, with an anticipated completion date of 2013. "^[13]

Route

See also

• The Wikimedia Commons has media related to M4 motorway. The term Central London refers to the districts of London England which are considered closest to the centre List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Chiswick ( IPA /ˈtʃɪzɪk/ is an area of West London, located west of Charing Cross, which covers the eastern part of the London Borough of Hounslow List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Chiswick ( IPA /ˈtʃɪzɪk/ is an area of West London, located west of Charing Cross, which covers the eastern part of the London Borough of Hounslow Staines is a Thames -side town in the Spelthorne borough of Surrey and part of the London Commuter Belt of South East England, Hounslow is the principal town in the London Borough of Hounslow. Brentford is a suburb in the London Borough of Hounslow at the Confluence of the River Thames and the River Brent in West London Heston services is a Motorway service station on the M4 motorway near London, built on land that once formed part of the now defunct Heston Aerodrome List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Hayes is a town in the London Borough of Hillingdon. It is a suburban development situated 13 miles (20 Harrow is a town in the London Borough of Harrow, North West London. Hounslow is the principal town in the London Borough of Hounslow. List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Hayes is a town in the London Borough of Hillingdon. It is a suburban development situated 13 miles (20 Harrow is a town in the London Borough of Harrow, North West London. Hounslow is the principal town in the London Borough of Hounslow. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Uxbridge is a university town in the London Borough of Hillingdon in West London, England. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Uxbridge is a university town in the London Borough of Hillingdon in West London, England. To see information about the M25 motorway under construction in Ireland, see N25 road. Gatwick Airport is London 's second largest Airport and the second busiest airport in the United Kingdom after Heathrow. Watford (ˈwɒtfəd) is a town and district in Hertfordshire, England, situated 19 miles (30 km northwest of London Oxford is currently bidding for the 2010 Wikimania Conference Oxford () is a city, and the County town of Oxfordshire, Winchester or Winton ( archaic) is a historic city in southern England, with a population of around 40000 within a radius of its centre The M40 Motorway is a motorway in the English Transport network that connects London to Birmingham. The M1 is a major south – north Motorway in England primarily connecting London to Leeds, where The M3 motorway is a Motorway in Hampshire and Surrey, England. The M23 motorway is a Motorway in England. The Motorway runs from south of Hooley in Surrey, where it splits from the To see information about the M25 motorway under construction in Ireland, see N25 road. Gatwick Airport is London 's second largest Airport and the second busiest airport in the United Kingdom after Heathrow. Watford (ˈwɒtfəd) is a town and district in Hertfordshire, England, situated 19 miles (30 km northwest of London Oxford is currently bidding for the 2010 Wikimania Conference Oxford () is a city, and the County town of Oxfordshire, Winchester or Winton ( archaic) is a historic city in southern England, with a population of around 40000 within a radius of its centre The M40 Motorway is a motorway in the English Transport network that connects London to Birmingham. The M1 is a major south – north Motorway in England primarily connecting London to Leeds, where The M3 motorway is a Motorway in Hampshire and Surrey, England. The M23 motorway is a Motorway in England. The Motorway runs from south of Hooley in Surrey, where it splits from the Colnbrook is a large Village in the Unitary authority of Slough, in Berkshire, England. Langley (also known as Langley Marish) is a Village in the unitary authority of Slough, Berkshire in South East England. B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind Eton is a Town in Berkshire, England, lying on the opposite bank of the River Thames to Windsor and connected to it by Windsor Datchet is an English Thameside village situated in the Unitary authority of Windsor and Maidenhead in the county of Berkshire Colnbrook is a large Village in the Unitary authority of Slough, in Berkshire, England. Langley (also known as Langley Marish) is a Village in the unitary authority of Slough, Berkshire in South East England. B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind Eton is a Town in Berkshire, England, lying on the opposite bank of the River Thames to Windsor and connected to it by Windsor Datchet is an English Thameside village situated in the Unitary authority of Windsor and Maidenhead in the county of Berkshire List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Slough ( ˈslaʊ is a Borough and Unitary authority within the ceremonial county of Berkshire, England. List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Windsor (ˈwɪnzə/ /ˈwɪndzə is a suburban town and tourist destination in the Royal Borough of Windsor and Maidenhead in Berkshire, England. List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Slough ( ˈslaʊ is a Borough and Unitary authority within the ceremonial county of Berkshire, England. List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Windsor (ˈwɪnzə/ /ˈwɪndzə is a suburban town and tourist destination in the Royal Borough of Windsor and Maidenhead in Berkshire, England. The A404(M is a Motorway in Berkshire, England and can be referred to as the Maidenhead West Bypass. See also High Wycombe Western Australia High Wycombe (hai ˈwɪk Henley-on-Thames is a town on the north side of the River Thames in south Oxfordshire, England, about 10 miles downstream and north-east from The A308(M is a Motorway in Berkshire, England. It is 06 Miles (1 Km) long and is possibly England's shortest motorway, although Maidenhead is a town within the Royal Borough of Windsor and Maidenhead, in Berkshire, England. The A404(M is a Motorway in Berkshire, England and can be referred to as the Maidenhead West Bypass. See also High Wycombe Western Australia High Wycombe (hai ˈwɪk Henley-on-Thames is a town on the north side of the River Thames in south Oxfordshire, England, about 10 miles downstream and north-east from The A308(M is a Motorway in Berkshire, England. It is 06 Miles (1 Km) long and is possibly England's shortest motorway, although Maidenhead is a town within the Royal Borough of Windsor and Maidenhead, in Berkshire, England. The A329(M is a Motorway in Berkshire, England. It is 4 Miles (6 Reading (ˈrɛdɪŋ as Redding) is a town in England, located at the confluence of the River Thames and River Kennet, midway between Bracknell is a town in the Bracknell Forest borough of Berkshire, England. The A329(M is a Motorway in Berkshire, England. It is 4 Miles (6 Reading (ˈrɛdɪŋ as Redding) is a town in England, located at the confluence of the River Thames and River Kennet, midway between Bracknell is a town in the Bracknell Forest borough of Berkshire, England. The A33 is a major Road in England. The road formerly ran from Reading to Southampton, but now consists of three disjoint sections Basingstoke is a town in northeast Hampshire, England It lies across a Valley at the source of the River Loddon. The A33 is a major Road in England. The road formerly ran from Reading to Southampton, but now consists of three disjoint sections Basingstoke is a town in northeast Hampshire, England It lies across a Valley at the source of the River Loddon. Reading services comprises a pair of adjacent Motorway Service areas on the M4 motorway to the south of the town of Reading in the English Theale is a large Village and Civil parish in the English county of Berkshire. Theale is a large Village and Civil parish in the English county of Berkshire. The A34 is a major road in England. It runs from the A6042 in Salford to Winchester in Hampshire. Newbury is a Civil parish and the principal Town in the west of the County of Berkshire in England. Oxford is currently bidding for the 2010 Wikimania Conference Oxford () is a city, and the County town of Oxfordshire, Chieveley services is a UK Motorway service station on the M4 motorway at Chieveley near Newbury in Berkshire. The A34 is a major road in England. It runs from the A6042 in Salford to Winchester in Hampshire. Newbury is a Civil parish and the principal Town in the west of the County of Berkshire in England. Oxford is currently bidding for the 2010 Wikimania Conference Oxford () is a city, and the County town of Oxfordshire, Route of Road The road begins in central Bournemouth before heading northward as a grade separated Dual carriageway, one of the main roads in the South For other uses see Hungerford (disambiguation Hungerford is a Market town and Civil parish in Berkshire, Wantage is a Town and Civil parish in the Vale of the White Horse, near the Thames Valley, in the English county of Oxfordshire Route of Road The road begins in central Bournemouth before heading northward as a grade separated Dual carriageway, one of the main roads in the South For other uses see Hungerford (disambiguation Hungerford is a Market town and Civil parish in Berkshire, Wantage is a Town and Civil parish in the Vale of the White Horse, near the Thames Valley, in the English county of Oxfordshire Membury services is a Motorway service station on the M4 motorway. The A419 road is a Dual carriageway Trunk road between Chiseldon near Swindon at junction 15 of the M4 with the A346 road Swindon ( is a large town in the ceremonial county of Wiltshire in the South West of England, midway between Bristol (64 km / 40 miles The A346 is a road in Wiltshire, southern England, that runs from Ludgershall to Swindon. Marlborough ( IPA /ˈmɔːlbrə/ " Maul bruh" is a market town in the English county of Wiltshire on the Old Bath Road The A420 is a road between Bristol and Oxford in England. Between Swindon and Oxford it is a Primary route. The A419 road is a Dual carriageway Trunk road between Chiseldon near Swindon at junction 15 of the M4 with the A346 road Swindon ( is a large town in the ceremonial county of Wiltshire in the South West of England, midway between Bristol (64 km / 40 miles The A346 is a road in Wiltshire, southern England, that runs from Ludgershall to Swindon. Marlborough ( IPA /ˈmɔːlbrə/ " Maul bruh" is a market town in the English county of Wiltshire on the Old Bath Road List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Swindon ( is a large town in the ceremonial county of Wiltshire in the South West of England, midway between Bristol (64 km / 40 miles Wootton Bassett is a small Market town located in northern Wiltshire, UK. RAF Lyneham is a Royal Air Force station in Wiltshire, England. Calne is a Town in central Wiltshire, England. It is situated at the southern extreme of the county's North Wiltshire * local government district List of A roads beginning with 3 in Great Britain starting west of the A3 and south of the A4. Swindon ( is a large town in the ceremonial county of Wiltshire in the South West of England, midway between Bristol (64 km / 40 miles Wootton Bassett is a small Market town located in northern Wiltshire, UK. RAF Lyneham is a Royal Air Force station in Wiltshire, England. Calne is a Town in central Wiltshire, England. It is situated at the southern extreme of the county's North Wiltshire * local government district The A350 is a north-south Primary route in southern England, that runs from the M4 motorway in Wiltshire to Poole in Dorset Chippenham is a Market town in Wiltshire, England, located at, some 21 km (13 miles east of Bath and 163 km (96 miles west of London The A429 is a main road in England that runs in a north-northeasterly direction from junction 17 of the M4 motorway (4 miles north of Chippenham in Cirencester is a Market town in Gloucestershire, England, 93 miles (150 km west northwest of London The A350 is a north-south Primary route in southern England, that runs from the M4 motorway in Wiltshire to Poole in Dorset Chippenham is a Market town in Wiltshire, England, located at, some 21 km (13 miles east of Bath and 163 km (96 miles west of London The A429 is a main road in England that runs in a north-northeasterly direction from junction 17 of the M4 motorway (4 miles north of Chippenham in Cirencester is a Market town in Gloucestershire, England, 93 miles (150 km west northwest of London Leigh Delamere is a Motorway service station on the M4 motorway situated one mile west of Junction 17 between Bristol and Swindon (close to The A46 is a Trunk road in England. It largely follows the course of the Roman Fosse Way, from Lincoln to south Devon. Bath is a city in Somerset in the south west of England It is situated west of London and south-east of Bristol. Stroud is a Town and Civil parish in the County of Gloucestershire, England. The A46 is a Trunk road in England. It largely follows the course of the Roman Fosse Way, from Lincoln to south Devon. Bath is a city in Somerset in the south west of England It is situated west of London and south-east of Bristol. Stroud is a Town and Civil parish in the County of Gloucestershire, England. The M32 is a Motorway in South Gloucestershire and Bristol, England. Bristol ( ˈbrɪstəl is a city, Unitary authority and ceremonial county in South West England, west of London The M32 is a Motorway in South Gloucestershire and Bristol, England. Bristol ( ˈbrɪstəl is a city, Unitary authority and ceremonial county in South West England, west of London This article is about the M5 motorway in England See M5 for other roads numbered "M5" This article is about the M5 motorway in England See M5 for other roads numbered "M5" This article is mainly about the English Midlands For other uses see Midlands (disambiguation. Gloucester (ˈɡlɒstɚ) is a city, district and County town of Gloucestershire in the South West region of England. The Almondsbury Interchange in South Gloucestershire, is one of the United Kingdom 's largest motorway Stack interchanges The interchange is one of only This article is about the M5 motorway in England See M5 for other roads numbered "M5" This article is about the M5 motorway in England See M5 for other roads numbered "M5" This article is mainly about the English Midlands For other uses see Midlands (disambiguation. Gloucester (ˈɡlɒstɚ) is a city, district and County town of Gloucestershire in the South West region of England. The M48 is a Motorway in Great Britain joining Gloucestershire and Monmouthshire over the original Severn Bridge. Chepstow (Cas-gwent is a town in Monmouthshire, Wales, adjoining the border with Gloucestershire, England. The M49 motorway is a small Motorway west of Bristol, England, that forms a shortcut between the M5 motorway and the Second Severn Avonmouth is a port and suburb on the Severn Estuary, at the mouth of the River Avon. Bridgwater in Somerset, England, is a Market town, the administrative centre of the Sedgemoor district, and the leading industrial Exeter ( (IPA ˈeksɪtər is a city, district and County town of Devon, England. The M49 motorway is a small Motorway west of Bristol, England, that forms a shortcut between the M5 motorway and the Second Severn Avonmouth is a port and suburb on the Severn Estuary, at the mouth of the River Avon. England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland The Second Severn Crossing ( Welsh: Ail Groesfan Hafren) is a Motorway crossing over the River Severn between England and Wales B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind Magor (Magwyr - meaning 'a wall' - is a large Village in Monmouthshire, south east Wales, between Chepstow and the city of Newport Caldicot (Cil-y-coed is a small Town in Monmouthshire, southeast Wales, located between Chepstow and Newport, just off the busy Magor services is a Motorway service station on the M4 motorway at Magor near Newport, south Wales. B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind Magor (Magwyr - meaning 'a wall' - is a large Village in Monmouthshire, south east Wales, between Chepstow and the city of Newport Caldicot (Cil-y-coed is a small Town in Monmouthshire, southeast Wales, located between Chepstow and Newport, just off the busy The A48 is a major Trunk road in Great Britain. It runs from the A40 at Highnam west of Gloucester to the A40 at Carmarthen Newport city centre is traditionally regarded as the area of Newport bounded by the west bank of the River Usk, the George Street Bridge, the eastern flank B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind Newport (Casnewydd is a city and principal area in Wales, in the United Kingdom. The A449 is a major road in the United Kingdom. It runs north from junction 24 of the M4 motorway at Newport in South Wales to Stafford This is about the Welsh town of Monmouth For other uses see Monmouth (disambiguation. For other uses see M50 motorway. The M50 is a Motorway in Gloucestershire, Worcestershire and Herefordshire The A48 is a major Trunk road in Great Britain. It runs from the A40 at Highnam west of Gloucester to the A40 at Carmarthen Newport city centre is traditionally regarded as the area of Newport bounded by the west bank of the River Usk, the George Street Bridge, the eastern flank B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind Newport (Casnewydd is a city and principal area in Wales, in the United Kingdom. The A449 is a major road in the United Kingdom. It runs north from junction 24 of the M4 motorway at Newport in South Wales to Stafford This is about the Welsh town of Monmouth For other uses see Monmouth (disambiguation. B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind Caerleon (Caerllion is a suburban village and community, situated on the River Usk in the northern outskirts of the city of Newport, South The A4042 is a Trunk road that runs from Abergavenny to Newport in the United Kingdom. Cwmbran (Cwmbrân is a New town in Wales within the historic boundaries of Monmouthshire, and within the modern County borough of The Brynglas Tunnels carry the M4 motorway under Brynglas Hill in Newport. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind High Cross is a Suburb of the City of Newport, South Wales in the United Kingdom, and forms part of the community (parish B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind High Cross is a Suburb of the City of Newport, South Wales in the United Kingdom, and forms part of the community (parish List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Alternate meanings see Risca (disambiguation. Risca (Rhisga is a Town of approximately 11500 people in Gwent South Wales within the historic See also Bryn Mawr (disambiguation for other places with this name List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Alternate meanings see Risca (disambiguation. Risca (Rhisga is a Town of approximately 11500 people in Gwent South Wales within the historic See also Bryn Mawr (disambiguation for other places with this name The A48(M is a Motorway in Wales between Cardiff and Newport. Cardiff ( 'kɑːdɪf) is the Capital and the largest city and county in Wales. The A4232, which is known either as the Peripheral Distributor Road (PDR (Ffordd Ddosbarthu Ymylol or the Cardiff Link Road (Ffordd Gyswllt Caerdydd is a Cardiff Gate services is the Motorway service station on the junction of the M4 motorway (junction 30 and the A4232 north east of Cardiff, The A4232, which is known either as the Peripheral Distributor Road (PDR (Ffordd Ddosbarthu Ymylol or the Cardiff Link Road (Ffordd Gyswllt Caerdydd is a The A470 is a major long-distance connective spine road in Wales, running from Cardiff on the south coast to Llandudno on the north coast Merthyr Tydfil today Government The current Borough boundaries date back to 1974 when the former county borough of Merthyr Tydfil expanded slightly to cover The A470 is a major long-distance connective spine road in Wales, running from Cardiff on the south coast to Llandudno on the north coast Merthyr Tydfil today Government The current Borough boundaries date back to 1974 when the former county borough of Merthyr Tydfil expanded slightly to cover Cardiff International Airport (Maes Awyr Rhyngwladol Caerdydd is the main airport for Wales serving around 2 million people in Cardiff and the rest of South and Barry (Y Barri is a Town in the Vale of Glamorgan, Wales. Located along the northern coast of the Bristol Channel less than 7 miles (11 kilometers Penarth is a Town in the Vale of Glamorgan (Bro Morgannwg Wales (Cymru 5 Cardiff West services is a Motorway service station on junction 33 of the M4 motorway and the Capel Llanilltern junction of the A4232 near Cardiff Cardiff International Airport (Maes Awyr Rhyngwladol Caerdydd is the main airport for Wales serving around 2 million people in Cardiff and the rest of South and Barry (Y Barri is a Town in the Vale of Glamorgan, Wales. Located along the northern coast of the Bristol Channel less than 7 miles (11 kilometers Penarth is a Town in the Vale of Glamorgan (Bro Morgannwg Wales (Cymru 5 List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Llantrisant is a Town in the County borough of Rhondda Cynon Taff, within the historic county boundaries of Glamorgan, Wales Rhondda ('rɒnðɘ or Rhondda Valley ( Welsh: Cwm Rhondda) is a former coal-mining valley in Wales, consisting of 16 communities built around List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Llantrisant is a Town in the County borough of Rhondda Cynon Taff, within the historic county boundaries of Glamorgan, Wales Rhondda ('rɒnðɘ or Rhondda Valley ( Welsh: Cwm Rhondda) is a former coal-mining valley in Wales, consisting of 16 communities built around List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Pencoed (pronounced "Pen-coyd" in English meaning 'end or head of the wood' is a Town in the County borough of Bridgend, List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Pencoed (pronounced "Pen-coyd" in English meaning 'end or head of the wood' is a Town in the County borough of Bridgend, Bridgend (Pen-y-bont ar Ogwr is a town in the Country Borough of Bridgend in Wales. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Maesteg is a town in the County Borough of Bridgend, Wales. It lies at the northernmost end of the Llynfi Valley, close to the border with the county Sarn Park services is a Motorway service station on the M4 motorway in Wales. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Maesteg is a town in the County Borough of Bridgend, Wales. It lies at the northernmost end of the Llynfi Valley, close to the border with the county List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Porthcawl is a Town on the south coast of Wales in the county borough of Bridgend, 25 miles (40 kilometres west of the Capital city, Pyle (Y Pîl is a village in Bridgend county borough, South Wales. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Porthcawl is a Town on the south coast of Wales in the county borough of Bridgend, 25 miles (40 kilometres west of the Capital city, Pyle (Y Pîl is a village in Bridgend county borough, South Wales. Port Talbot ( Welsh: Aberafan or Porth Talbot) is an Industrial Town in south Wales, UK, with a Population Port Talbot ( Welsh: Aberafan or Porth Talbot) is an Industrial Town in south Wales, UK, with a Population List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Briton Ferry (Llansawel is a Town and community in the County borough of Neath Port Talbot, Wales. The A483 is a major road in the United Kingdom, running from Swansea in Wales to Chester in England. Swansea ( Abertawe "mouth of the Tawe " is a city and county in Wales. The A483 is a major road in the United Kingdom, running from Swansea in Wales to Chester in England. Swansea ( Abertawe "mouth of the Tawe " is a city and county in Wales. The A465 is a major Road in south Wales. It is more commonly known as the Heads of the Valleys Road because it joins together the north ends Neath (Castell-nedd is a Town and community situated in the principal area of Neath Port Talbot, Wales, UK with a Merthyr Tydfil today Government The current Borough boundaries date back to 1974 when the former county borough of Merthyr Tydfil expanded slightly to cover The A465 is a major Road in south Wales. It is more commonly known as the Heads of the Valleys Road because it joins together the north ends Neath (Castell-nedd is a Town and community situated in the principal area of Neath Port Talbot, Wales, UK with a Merthyr Tydfil today Government The current Borough boundaries date back to 1974 when the former county borough of Merthyr Tydfil expanded slightly to cover The A4067 road is an A road connecting Swansea with Sennybridge in Wales. Pontardawe ( Welsh for "bridge on the River Tawe " is a Town of some 5000 inhabitants in the Swansea Valley (Welsh Cwmtawe Morriston ( Welsh: Treforys) is a Town in the City and County of Swansea, Wales and falls within the Morriston ward. Clydach is a town in the City and County of Swansea, Wales, falling within the Clydach ward The A4067 road is an A road connecting Swansea with Sennybridge in Wales. Pontardawe ( Welsh for "bridge on the River Tawe " is a Town of some 5000 inhabitants in the Swansea Valley (Welsh Cwmtawe Morriston ( Welsh: Treforys) is a Town in the City and County of Swansea, Wales and falls within the Morriston ward. Clydach is a town in the City and County of Swansea, Wales, falling within the Clydach ward B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind The village of Llangyfelach is located in the City and County of Swansea, Wales, UK. B roads are numbered routes in Great Britain of lesser importance than A roads See the article Great Britain road numbering scheme for the rationale behind The village of Llangyfelach is located in the City and County of Swansea, Wales, UK. Pontarddulais ( is a Town in the City and County of Swansea, Wales, known by locals as "The Bont" Penllergaer (Penlle'r-gaer is a Village in the City and County of Swansea, Wales, UK falling within the Penllergaer ward. Gorseinon is a town in south west Wales, near the Loughor estuary. Swansea services is a Motorway service station on the M4 motorway at Junction 47 near Penllergaer, Swansea, Wales. Pontarddulais ( is a Town in the City and County of Swansea, Wales, known by locals as "The Bont" Penllergaer (Penlle'r-gaer is a Village in the City and County of Swansea, Wales, UK falling within the Penllergaer ward. Gorseinon is a town in south west Wales, near the Loughor estuary. List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Llanelli ( English: Church of St Elli) pron, the largest Town in the County of Carmarthenshire, in south-west List of A roads beginning with 4 in Great Britain starting north of the A4 and south/west of the A5. Llanelli ( English: Church of St Elli) pron, the largest Town in the County of Carmarthenshire, in south-west Pont Abraham services is a Motorway service station on the M4 motorway in Wales. Carmarthen ( Welsh Caerfyrddin - caer fort + Myrddin Moridunum is the County town of Carmarthenshire, Wales. Ammanford ( Rhydaman) is the third largest Town in the County of Carmarthenshire, Wales, with a population 5299 according to
• New M4
• M4 Thames Bridge, Maidenhead
• A404(M) motorway
• M4 corridor
• List of motorways in the United Kingdom
• A48(M) motorway
• Transport in Wales

References

External links

• CBRD Motorway Database - M4
• British Road Database: Motorways - M4 Junction 8/9
• The Motorway Archive
  • Junctions 1 to 5
  • Junctions 5 to 7
  • Junctions 8 to 14
  • Junctions 14 to 21
  • Junctions 21 to 23
  • Junctions 23 to 49