M4 J1 Chiswick Roundabout

Layout and signage

Central London
Hammersmith
A4
 

A315

A406
   

A205
  N/A

Lane configuration

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  • Lane 1 is gained from the entry sliproad.
  • Lane 2 continues ahead.
  • Lane 3 continues ahead.

LanesLanesLanesLanesLanes

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

Other events

  • Signs End of motorway regulations
  • Signs 40mph speed limit begins
  • Signs Start of motorway regulations
  • Signs 40mph speed limit begins

In this section

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.

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.

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