M25 J21A Bricket Wood Interchange

Route

M25 and A282

Junction number

21A

Markerpost

123.8

Name

Bricket Wood Interchange

Terminus

Not a terminus

Other routes

A405

Authority

National Highways

Restricted turns

Full access

Services

No services

Layout and signage

Watford
Harrow
A405
London (NW)
(M1 S Link)
  A405


    A405


  St Albans
A405
London (NW)
(M1 S Link)

Lane configuration

LanesLanesLanesLanesLanesLanes

  • Lane 1 exits and does not return.
  • Lane 2 continues ahead.
  • Lane 3 continues ahead.
  • Lane 4 continues ahead.

LanesLanesLanesLanesLanesLanes

  • Lane 1 is gained from the entry sliproad.
  • Lane 2 continues, with option to exit.
  • Lane 3 continues ahead.
  • Lane 4 continues ahead.

Other events

  • Signs Variable Speed Limits apply
  • Signs Variable Speed Limits apply

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About this page

Published22 April 2017

Last updated3 May 2022