Congestion built up along many parts of the route in the south, the Midlands, Bedfordshire and Nottinghamshire.

"There have been some very long tailbacks indeed today and it's hardly a good way to mark the 40th anniversary," said RAC spokesman Rob Maynard.

The BBC's Jon Kay: "Road heralded a golden age of motoring"

The main route from London to Leeds was opened by Ernest Marples, minister for transport on 2 November 1959.

It was planned as the road of the century, a superhighway connecting north and south.

On its first day the motorway carried 13,000 vehicles - with some 100 cars breaking down along the way.

Then: Drivers warned not to picnic on the hard shoulder

In those days there were no speed limits and no MOT, and the rules of the motorway had to be drummed into drivers - who were warned against parking on the hard shoulder and having picnics.

"We had no streetlighting, no crash barriers on the motorway at all and no traffic really, only people coming along trying their cars out for speed," said Ray Maslin, a now retired police officer who worked on the M1.

The first 72-mile section from St Albans to Birmingham cost �28.5m and took 19 months to build, with one mile laid every eight days.

It was only designed to cope with 12,000 vehicles a day and was conceived as a freight route.

Now the 187-mile-long route carries one million vehicles a week, and an average of 88,000 vehicles a day.

Newport Pagnell was the M1's first service station - on its opening day it served just 50 lunches.

Now it pours 50,000 cups of tea a week and seven million people pass through the site every year.

Forty years on, congestion on the M1 has never been worse.

But the public transport-friendly policies of the current government mean the road is unlikely to see major investment.

Experts predict it will survive the next 40 years.

"I don't think the M1 is going to come to an end because there will still be substantial numbers of people who want to drive," said Professor Stuart Coles of the University of North London.