A computer expert from Epsom has shaved 43 minutes off the record for visiting all 275 stations on the London Underground railway network.

Geoff Marshall, 32, and his companion Neil Blake, 31, dashed through the 225-mile tube network in 18 hours, 35 minutes and 43 seconds.

While jaded commuters consider the Tube a nightmare to be endured, Mr Marshall has made a mastery of its tunnels a personal quest since taking up the challenge for charity in May 2002.

His previous six attempts foundered because of missed connections, a heatwave, breakdowns and a knee injury. On this occasion he trained for six days to get fit and to identify the ideal itinerary using the Tube's 12 lines.

Mr Marshall, who took more than 300 pictures at stations and kept a logbook detailing the record, said: "I like the pointlessness of the record. It's a bit of fun that has become an obsession.

"Everybody thinks it's just about sitting on trains but I've being going to the gym because a lot of it is running from one end to the other."

"By the time it got to 9pm and we had beaten the rush hour, I was very calm. Everything worked out swimmingly."

The men are keeping their route secret, to protect the record. But their journey is understood to have begun shortly before 5.30am at Amersham on the Metropolitan Line and ended just after midnight at Upminster on the District Line eight stops beyond Barking.

Paradoxically, the two completed their journey so late that they missed the last Tube home and had to hire a minicab.

kbarnes@london.newsquest.co.uk