The history of the M1 motorway, which is celebrating its 50th anniversary, is that of motoring’s loss of innocence. When the UK’s first autobahn opened, it was a miracle of civil engineering that would bear Britons out of austerity and into a prosperous tomorrow. Today it is too often a free-form car park from which the peripatetic business person calls with the dread words “I don’t know when I’ll get there. I’m stuck on the M1.”

The first few Wolseleys and Morrises that bowled along the London-Yorkshire Highway did so nervously. Police patrolmen stopped the worst offenders and cautioned them to drive faster.