A3

A3 and A3(M)

London to Portsmouth

The A3 is the historic route south-west from London to Portsmouth, connecting the capital with the home of the navy, and thanks to a steady programme of upgrades since the early part of the 20th Century, it still is, and today it's virtually a motorway from the city to the coast.

Routes

A3

The A3 has been one of London's most important approaches for centuries. Planned upgrades in the sixties were almost all built, but not quite, making a very fast road that fizzles out at Wandsworth.

Routes
A3

What's new

South London's lost motorways

Completing the story of London's epic Ringways, we've just published the Southern Radials, five more motorways that never saw the light of day.

To the north east!

Two new additions to our collection of Opening Booklets take us to Darlington and Middlesbrough.

The ghost junction

The only UK motorway that didn’t connect to ordinary roads finally got its own interchange in 2019. But it's not open, because it still doesn’t touch any ordinary roads.

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