Route
Junction number
1A
Markerpost
32.5 km
Name
Denham Interchange
Terminus
Not a terminus
Other routes
M25
Authority
Restricted turns
Full access
Services
No services
M40 J1A Denham Interchange
Layout and signage
Lane configuration
- Lane 1 is gained from the entry sliproad.
- Lane 2 continues, with option to exit.
- Lane 3 continues ahead.
- Lane 4 continues ahead.
- Lane 1 exits and does not return.
- Lane 2 exits and does not return.
- Lane 3 splits to create a new lane.
- Lane 4 continues ahead.
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.
Have you seen...
North Cross Route
The route and the history of the North Cross Route, proposed in the 1960s as the northern side of London's innermost motorway ring road.
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Published
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