Revealed after 50 years: The secret of the greatest-ever student prank

It was probably the most ingenious student prank of all time.

In June 1958, Cambridge awoke to see a car perched at the apex of an inaccessible rooftop, looking as if it were driving across the skyline.

The spectacle made headlines around the world and left police, firefighters and civil defence units battling for nearly a week to hoist the vehicle back down before giving in and taking it to pieces with blowtorches.

The shadowy group of engineering students who executed the stunt were never identified and the mystery of how they did it has baffled successive undergraduates and provided fodder for countless tourist guides.

Now, 50 years on, the group have reunited to disclose their identities and reveal how they winched an Austin Seven to the top of the university's 70ft-high Senate House.

At an anniversary dinner this month, ringleader Peter Davey revealed he had hatched the plan while staying in rooms at Gonville and Caius College overlooking the Senate House roof.

He felt the expanse of roof 'cried out' to be made more interesting and decided a car would do the trick, recruiting 11 others to help realise his plan.

The group chose the May Bumps week, when any passers-by were likely to be drunken rowers celebrating after their races.

After finding a clapped-out Austin Seven, the group had to tow it through Cambridge to a parking space near Senate House but hit on the idea of sticking signs on it advertising a May ball to explain its presence.

Mr Davey, now 72, said a ground party manoeuvred the car into position while a lifting party on the Senate House roof hoisted it up using an A-shaped crane constructed from scaffolding poles and steel rope.

A third group, the bridge party, passed a plank across the notorious Senate House Leap - an 8ft gap between the roof and a turret window at Caius - and helped the lifters ferry across lifting gear comprising three types of rope, hooks and pulleys.

Policemen who heard a commotion as the equipment passed above them questioned some of the ground party but were distracted by careless drivers nearby and left them alone.