A470 Glyntaff Interchange

Layout and signage

Llantrisant
(A473)
  B4595

A4054
    A4054  

Lane configuration

LanesLanesLanesLanes

  • Lane 1 continues, with option to exit.
  • Lane 2 continues ahead.

In this section

What's new

The monster seen from below

What might it have been like to stand in one spot and witness the arrival, and the uncertainty, of plans for an urban motorway in West London?

The road that made no sense

It was the UK's only single-carriageway motorway, and twenty years ago it ceased to exist. This is the story of the strange fascination it held, and of my place in history.

The forever bottleneck, part 2

The second part of the story, where we learn why exactly the M4 gets narrower on the final approach to Europe’s biggest city.

Share this page

Have you seen...

Operation Stack

If there's trouble crossing the Channel, you'll see the lorries queuing on the M20. What is Operation Stack? Why does it cause so much trouble? And why, more than twenty years after it started, are we still using it?

About this page

Published

Last updated