M4 J3 Cranford Parkway Interchange

Layout and signage

Heathrow Airport
Harrow
Hounslow
A312
  A312     A312   Heathrow Airport T4 & Cargo
Feltham
Hayes
A312

Lane configuration

LanesLanesLanesLanesLanesLanes

  • Lane 1 exits and does not return.
  • Lane 2 continues ahead.
  • Lane 3 continues ahead.
  • Lane 4 continues ahead.

LanesLanesLanesLanesLanesLanes

  • 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

  • Signs 60mph speed limit begins
  • Signs Variable Speed Limits apply

In this section

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London, in a new light

It was specially designed never to be noticed. And now it's disappearing, nobody has noticed its absence. It's London's own bespoke street light.

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Ringways

The story of an incredible plan to reshape London into a city of motorways, with the history from creation to cancellation and details on every unbuilt road.

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