A1(M) J1 South Mimms Interchange

Layout and signage

Stansted Airport (M11 Link)
Dartford Tunnel (M20 Link)
Heathrow Airport (M4 Link)
M25 Link
Barnet A1081
Services South Mimms
  M25
(M4)
   

M25
(M11)
(M20)

A1081
  Stansted Airport (M11 Link)
Dartford Tunnel (M20 Link)
Heathrow Airport (M4 Link)
M25 Link
Barnet A1081
Services South Mimms

Lane configuration

LanesLanesLanesLanesLanes

  • Lane 1 exits and does not return.
  • Lane 2 continues ahead.
  • Lane 3 continues ahead.

LanesLanesLanesLanesLanes

  • Lane 1 is gained from the entry sliproad.
  • Lane 2 continues, with option to exit.
  • Lane 3 continues ahead.

Other events

  • Signs Start of motorway regulations
  • Signs End of motorway regulations

In this section

What's new

The sunlit uplands

On Saturday 31 May something historic happened. The Heads of the Valleys Road was finally complete.

Grand openings

Our much-loved Opening Booklets section has two new publications for you to explore, and we’re making some overdue changes to make them easier to find and easier to read.

Silver bullet

The Silvertown Tunnel is finally open for business. One question remains: what’s it for?

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Daniel "Swampy" Hooper

Britain's most famous anti-road protester, who shot to fame in the mid-1990s and came to represent the whole environmental movement.

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