A1(M) J1 South Mimms Interchange

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Route

A1 and A1(M)

Junction number

1

Markerpost

23

Name

South Mimms Interchange

Type

Three Level Stacked Roundabout

Terminus

Not a terminus

Other routes

M25

Authority

Highways England

Restricted turns

Full access

Services

Service area here

Service area name

South Mimms

Services operator

Welcome Break

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

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