M4 J4 Airport Interchange

Layout and signage

Uxbridge
Heathrow Airport T2 & 3
A408
  (A408)     (A4)   Heathrow Airport T2 & 3
Uxbridge
A408

Lane configuration

LanesLanesLanesLanesLanesLanesLanes

  • Lane 1 exits and does not return.
  • Lane 2 continues ahead.
  • Lane 3 continues ahead.
  • Lane 4 continues ahead.
  • Lane 5 continues ahead.

LanesLanesLanesLanesLanesLanesLanes

  • Lane 1 is gained from the entry sliproad.
  • Lane 2 continues, with option to exit.
  • Lane 3 continues ahead.
  • Lane 4 continues ahead.
  • Lane 5 continues ahead.

Other events

  • Signs Variable Speed Limits apply
  • Signs Variable Speed Limits apply

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