An intrepid trio of travellers from Didcot went underground to raise £3,500 for a charity pre-school.

Alan Perks, with friends John Holman and Julian Coles, visited all 274 London tube stations in 19 hours 37 minutes. They started their epic journey at Amersham at 5.28am, and finally finished at 1.05am the following morning at Upminster.

They raised more than £1,750 for Park Pre-School in Queensway and their employer Excel logistics has agreed to double the total.

Mr Perks, of Norrey's Road, said: "It is extremely tiring, every time you change you're running up stairs and escalators or running down streets in the rain. We didn't even stop for a cup of tea all day."

The team spent a week planning their route with military precision. And the schedule was so tight just one delayed train or even a vandalised toilet could put the attempt in jeopardy.

It is the second time Mr Perks has attempted the challenge. In 2005 he visited 236 stations in a day, raising more than £3,000 for the pre-school.