M4 J25A Grove Park Interchange

Layout and signage

River or canal Usk   A4042

      Casnewydd — Newport
Cwmbran
A4042
River or canal Usk

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.

In this section

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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.

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