Route
Junction number
21A
Markerpost
123.8 km
Name
Bricket Wood Interchange
Terminus
Not a terminus
Other routes
A405
Authority
Restricted turns
Full access
Services
No services
M25 J21A Bricket Wood Interchange
Layout and signage
Lane configuration
- Lane 1 exits and does not return.
- Lane 2 continues ahead.
- Lane 3 continues ahead.
- Lane 4 continues ahead.
- 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
Variable Speed Limits apply
- Variable Speed Limits apply
What's new
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The forever bottleneck, part 1
The M4 into London was one of the UK's earliest and most ambitious motorway projects. It was bold, pioneering... and almost instantly regretted.
Have you seen...
London Congestion Charge
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About this page
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Last updated
Published
Last updated
