Route
Junction number
8
Markerpost
30.8 km
Name
Merstham Interchange
Type
Terminus
Not a terminus
Other routes
M25
Authority
Restricted turns
Full access
Services
No services
M23 J8 Merstham Interchange
Layout and signage
(M4 
Lane configuration
- Lane 1 exits and does not return.
- Lane 2 exits and returns after the junction.
- Lane 3 continues ahead.
- Lane 4 continues ahead.
- Lane 1 exits and returns after the junction.
- Lane 2 exits and returns after the junction.
- Lane 3 continues ahead.
- Lane 4 continues ahead.
Other events
National Speed Limit begins
Variable Speed Limits apply
What's new
The forever bottleneck, part 2
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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.
Hello, here's my ridiculous side project
An introduction to what I write, and why I write it, and where my strange new road sign simulator fits in to all this.
Have you seen...
Alley by gaslight
Some of Central London's quieter streets are still, surprisingly, lit by old and rather beautiful gas lanterns. Here are a few, by day and by night.
About this page
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Last updated
Published
Last updated
