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M25 motorway

2007 Schools Wikipedia Selection. Related subjects: Geography of Great
Britain; Road transport

                                      M25 motorway
                                        Length        117 miles
                                                         188 km
                                     Direction         Circular
                                         Start         Dartford
                          Primary destinations London
                                                                  Dartford
                                                                   Bromley
                                                                 Sevenoaks
                                                           Gatwick Airport
                                                                   Reigate
                                                                   Dorking
                                                                     Esher
                                                                   Staines
                                                          Heathrow Airport
                                                                   Watford
                                                           Hemel Hempstead
                                               Stansted Airport
                                           End    West Thurrock
                            Construction dates      1975 - 1986
                              Motorways joined 3 -
                                                       M20 motorway
                                                                5 -
                                                       M26 motorway
                                                                7 -
                                                       M23 motorway
                                                               12 -
                                                        M3 motorway
                                                               15 -
                                                        M4 motorway
                                                               16 -
                                                       M40 motorway
                                                               21 -
                                                        M1 motorway
                                                               23 -
                                                     A1(M) motorway
                                                               27 -
                                                   M11 motorway

   The M25 motorway looking south between junctions 14 and 15, near
   Heathrow Airport. The red light from the overhead gantry, just visible
   in the distance, is the MIDAS system indicating a reduced speed limit
   due to congestion
   Enlarge
   The M25 motorway looking south between junctions 14 and 15, near
   Heathrow Airport. The red light from the overhead gantry, just visible
   in the distance, is the MIDAS system indicating a reduced speed limit
   due to congestion
   The M25 between junction 24 (Potters Bar) and 25 (Waltham Cross).
   Enlarge
   The M25 between junction 24 ( Potters Bar) and 25 (Waltham Cross).

   The M25 motorway is one of the United Kingdom's motorways. It is an
   orbital motorway, 117 miles (188 km) in circumference, that almost
   completely encircles London (the gap is formed in the east, with the
   Dartford Crossing or the A282, linking two sides of the River Thames).
   It is said to be one of the longest city bypasses in the world. In
   Europe the M25 is the second-longest ring road after the Berlin Ring (
   A 10).

Description

   For most of its length the motorway has six lanes (three in each
   direction), although there are a few short stretches which are
   four-lane and perhaps one sixth is eight-lane, around the south-western
   corner. The motorway was widened to ten lanes between junctions 12 and
   14, and twelve lanes between junctions 14 and 15, in November 2005. The
   Highways Agency has plans to widen almost all of the remaining
   stretches of the M25 to eight lanes.

   It is one of Europe's busiest motorways, with 196,000 vehicles a day
   recorded in 2003 between junctions 13 and 14 near London Heathrow
   Airport ( ), significantly less, however, than the 257,000 vehicles a
   day recorded in 2002 on the A4 motorway at Saint-Maurice, in the
   suburbs of Paris ( ), or the 216,000 vehicles a day recorded in 1998 on
   the A 100 motorway near the Funkturm in Berlin ( ).

   The M25 is not a continuous loop. To the east of London, the toll
   crossing of the Thames between Thurrock and Dartford is the
   non-motorway A282. The Dartford Crossing, which consists of two tunnels
   and the QE2 (Queen Elizabeth II) bridge, is named Canterbury Way.
   Passage across the bridge or through the tunnels is subject to a toll,
   dependent upon the type of vehicle. Designating this stretch as a
   motorway would mean that traffic not permitted to use motorways could
   not cross the Thames east of Woolwich.

   While this is more a structural than a logical issue, at junction 5
   near Sevenoaks continuing around the M25 requires the driver to follow
   the slip roads, as the anticlockwise carriageway continues as the M26
   to the east (towards the M20) and the clockwise as the A21 towards the
   south coast.

   The road passes through multiple police force areas. Junctions 1–5 are
   in Kent, 6–14 in Surrey (passing at places through Greater London and
   Berkshire), 15–16 are in Buckinghamshire, 17–24 are in Hertfordshire,
   25 in Greater London, 26–28 in Essex, 29 in Greater London and 30–31 in
   Essex. Policing the road is carried out by an integrated policing group
   made up of the Metropolitan, Thames Valley, Essex, Kent, Hertfordshire
   and Surrey forces.

   The distance of the motorway from central London (taken as Charing
   Cross) varies from approximately 12 miles (20 km) near Potters Bar to
   20 miles (32 km) near Byfleet. In some places (Enfield, Hillingdon and
   Havering) the Greater London boundary has been aligned to the M25 while
   in others, most notably in Surrey, it is many miles distant. North
   Ockendon is the only settlement of Greater London to be outside the
   M25. In 2004, following a poll, a move was mooted by the London
   Assembly to entirely align the Greater London boundary to the M25.

History

   The idea of an orbital road around London was first proposed early in
   the 20th century and was re-examined a number of times during the first
   half of the 20th century inclunding in Sir Edwin Lutyens and Sir
   Charles Bressey's The Highway Development Survey, 1937 smd Sir Patrick
   Abercrombie's County of London Plan, 1943 and Greater London Plan,
   1944. Abercrombie's plan proposed a series of five roads ringing the
   capital.

   In the post-war years little was done to implement Abercrombie's plans
   but in the 1960s the Greater London Council developed an ambitious plan
   for a network of ring roads around the capital. The London Ringways
   plan was hugely controversial due to the destruction required for the
   inner two ring roads and the enormous anticipated cost. The plan was
   modified a number of times to overcome opposition from the residents of
   threatened areas and the government, but was cancelled in 1973. Parts
   of the two outer ring roads, Ringways 3 and 4, were begun in 1973 and
   became the first two sections of the M25 to open in 1975 (junction1 23
   to junction 24) and 1976 (junction 6 to junction 8).

   Construction of the M25 continued in stages until its completion in
   1986. The stages were not constructed contiguously but in small
   sections, such as Dartford to Swanley (junction 1 to junction 3) and
   Potters Bar to Waltham Cross (junction 24 to junction J25). As the
   orbital road developed the sections were linked. Each section was
   presented to planning authorities in its own right and was individually
   justified; there were almost 40 public inquiries relating to sections
   of the route. Maps at this time depicting these short sections named
   the route as the M16 but this changed prior to completion. The north
   sections of the M25 follow a similar route to the World War II Outer
   London Defence Ring.

   The M25 was officially opened on October 29, 1986 with a ceremony by
   Prime Minister Margaret Thatcher opening the section between J22 and
   J23 ( London Colney and South Mimms).

   The initial tenders for the construction of the M25 totalled £631.9
   million. This did not include compulsory purchase of land and
   subsequent upgrades and repairs.

   More recently, the perennially congested south-western stretch of the
   M25 (near Woking) has been fitted with an experimental automated
   traffic control system called Motorway Incident Detection and Automatic
   Signalling (MIDAS). This consists of a distributed network of traffic
   and weather sensors, speed cameras and variable-speed signs that
   control traffic speeds with little human supervision. The system has
   reduced congestion and it is hoped that MIDAS will be fitted to the
   rest of the M25 in due course.

   A precursor of the M25 was the North Orbital Road.

Illuminated sections

   Large sections of the M25 are illuminated with the aim of reducing
   accidents on the road. The current illuminated sections are Dartford to
   junction 2, junction 5, junctions 6 to 16, junctions 18 to 21A, and
   junctions 23 to 31. It is thought that when the widening of the M25 is
   completed junctions 3 to 5 will be the only area unlit, as this is the
   quietest part of the M25. The type of lights on the M25 varies, with
   some of the sections using the older yellow low pressure Sodium (SOX)
   lighting, and others with modern high pressure Sodium (SON) lighting.

Junctions

   The multi level junction with the M23.
   Enlarge
   The multi level junction with the M23.
                                M25 Motorway
                Anticlockwise exits Junction Clockwise exits
                       Erith A206 J1a Swanscombe A206
                          Dartford A225 J1b No Exit
                        London, Canterbury A2, ( M2)
               Dartford (A225) J2 London, Canterbury A2, (M2)
                           London (South East) A20
                                Maidstone M20
            Swanley B2173 J3 Maidstone, Channel Tunnel, Dover M20
                      London (South East), Swanley A20
                                 Bromley A21
                        Orpington A224 J4 Bromley A21
                               Orpington A224
                 Maidstone, Channel Tunnel, Dover M26 (M20)
             Sevenoaks, Hastings A21 J5 Sevenoaks, Hastings A21
                            Clacket Lane services
             East Grinstead, Eastbourne, Caterham, Godstone A22
   Westerham ( A25) J6 East Grinstead, Eastbourne, Caterham, Godstone, A22
                                Redhill (A25)
     Gatwick Airport, Crawley, Brighton, East Grinstead, Croydon M23 J7
               Gatwick Airport, Crawley, Brighton, Croydon M23
                            Reigate, Sutton A217
                    Redhill (A25) J8 Reigate, Sutton A217
                              Kingston ( A240)
                              Leatherhead A243
                     Dorking ( A24) J9 Leatherhead A243
                                Dorking (A24)
    London (South West), Kingston, Guildford A3 J10 London (South West),
                                Guildford A3
                                Chertsey A317
                         Woking A320 J11 Woking A320
                                Chertsey A317
     Basingstoke, Southampton, Sunbury M3 J12 Basingstoke, Southampton,
                                 Sunbury M3
                 Staines A30 J13 London (West), Staines A30
   Heathrow Airport (Terminals 4, 5 and Cargo) A3113 J14 Heathrow Airport
                      (Terminals 4, 5 and Cargo) A3113
    The WEST, Slough, Reading, London (West), Heathrow Airport (Terminals
    1, 2 and 3) M4 J15 The WEST, Slough, Reading, London (West), Heathrow
                      Airport (Terminals 1 2, and 3) M4
   Birmingham, Oxford, Uxbridge, London (West) M40 J16 Birmingham, Oxford,
                         Uxbridge, London (West) M40
          Maple Cross ( A412) J17 Maple Cross, Rickmansworth (A412)
     Rickmansworth, Chorleywood, Amersham A404 J18 Chorleywood, Amersham
                                    A404
                           No Exit J19 Watford A41
      Hemel Hempstead, Aylesbury A41 J20 Hemel Hempstead, Aylesbury A41
                                    A4251
       The NORTH, Luton & Airport M1 J21 The NORTH, Luton & Airport M1
                                Watford A405
                   Harrow (M1 South) J21A St. Albans A405
                      London (North West) (M1 (South))
                    St. Albans A1081 J22 St. Albans A1081
                               Hatfield A1(M)
                           London (North West) A1
                                Barnet A1081
                   South Mimms services J23 Hatfield A1(M)
                           London (North West) A1
                                Barnet A1081
                            South Mimms services
                    Potters Bar A111 J24 Potters Bar A111
               Enfield, Hertford A10 J25 Enfield, Hertford A10
        Waltham Abbey, Loughton A121 J26 Waltham Abbey, Loughton A121
   London (North East), Stansted Airport, Harlow, Cambridge M11 J27 London
            (North East), Stansted Airport, Harlow, Cambridge M11
                     Chelmsford, Witham, Colchester A12
                 Brentwood A1203 J28 Chelmsford, Romford A12
                               Brentwood A1023
        Romford, Basildon, Southend A127 J29 Basildon, Southend A127
                      Thurrock ( Lakeside), Tilbury A13
     Thurrock services J30 Dagenham, Thurrock (Lakeside), Tilbury A13, (
                             A1306, A126, A1090)
                              Thurrock services
                 South Ockendon, Dagenham A1306 J31 No Exit

Trivia

   The M25 (including the A282 Dartford Crossing) is known for its
   frequent jams. These have been the subject of so much comment from such
   an early stage that even at the official opening ceremony Margaret
   Thatcher complained about "those who carp and criticise". The jams have
   inspired jokes ("the world's biggest car park"), songs ( Chris Rea's
   "The Road to Hell") and the following tongue-in-cheek theory:

          "Many phenomena — wars, plagues, sudden audits — have been
          advanced as evidence for the hidden hand of Satan in the affairs
          of Man, but whenever students of demonology get together the M25
          London orbital motorway is generally agreed to be among the top
          contenders for exhibit A."

                — from Good Omens, by Terry Pratchett and Neil Gaiman.

   The M25's name inspired the name of the electronica duo, Orbital.
   Retrieved from " http://en.wikipedia.org/wiki/M25_motorway"
   This reference article is mainly selected from the English Wikipedia
   with only minor checks and changes (see www.wikipedia.org for details
   of authors and sources) and is available under the GNU Free
   Documentation License. See also our Disclaimer.
