Nine riders, 24 hours, climbing Alpe d’Huez – on a Boris Bike.

Last weekend, a group of friends left the capital with nine of London’s Santander Cycles hire bikes and a challenge to drive to the Alps, climb one of the Tour de France’s most iconic and toughest ascents, and return within 24 hours.

The team, organised by London-based clothing brand Huez*, undertook the challenge, which took its inspiration from a similar feat on Mont Ventoux in 2013,  to raise money for the Stroke Association and The National Brain Appeal ahead of Stroke Awareness Month in May.

The group climbed the 21 hairpins of Alpe d’Huez, which rises for 13.8km at a grueling average gradient of 8.1 per cent and with long pitches over 11 per cent, in one hour and forty minutes – no mean feat on a three-geared bike with heavy, fat tyres and weighing 23kg in all.

However, the team returned to London in just over 24 hours, having been held up by a train delay – and getting pulled over by the French police.

“It was a long but unbelievably rewarding day,” said Huez* founder Lorenzo Curci. “Everyone did incredibly well and we are really pleased to have raised all this money for the vital work that the Stroke Association and The National Brain Appeal does.

“It’s a shame that a delay with the train to France and a stop by the French police meant we complete the challenge quite in 24 hours but we’re still really happy with the result.”

The team has so far raised over £17,000 for the two charities with the aim to reach more than £50,000. Visit http://uk.virginmoneygiving.com/HUEZ24HR to pledge your support.