A421

A421

St Neots to Milton Keynes

Since 1996, three sections of a new A421 expressway have been built, progressively completing a fast route that serves to link Cambridge to Milton Keynes and Bedford to the wider world.

Routes

What's new

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.

The forever bottleneck, part 1

The M4 into London was one of the UK's earliest and most ambitious motorway projects. It was bold, pioneering... and almost instantly regretted.

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Have you seen...

From War to Worboys

The tale of how British traffic signing developed between the Second World War and the mid-1960s, bringing us from a system designed at the turn of the century to the signs we still use today.