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

A century of motorways

It's 100 years since the opening of the world's first motorway, the Autostrada from Milan to the Lakes.

Schrödinger’s speed limit

In 2022, Manchester City Council say they reduced the speed limit on the Mancunian Way to 30mph. But it’s not clear if they did. It’s not even clear if they can.

Sorry, wrong number

Road numbering is a system with clear rules. What happens when the people responsible for numbering roads don't follow them?

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Have you seen...

Croydon Ring Road

Common sense suggests that you shouldn't be able to spend so much money on heavy engineering and end up with such a terrible road system.