Shona Thomson, 34, gave up a top job as an investment banker to run a marathon at the North Pole and face the dangers of polar bears, frost bite and hypothermia.
She has joined an elite band of intrepid adventurers, including Sir Ranulph Fiennes, who are part of the 'Seven Marathons Continents Club'. There are fewer than 100 members and less than 20 women - all of whom have run a marathon on every continent across the globe. But Ms Thomson, originally from Craigmaddie, near Glasgow, but who now lives in London, told how the latest event at the top of the world in -30C temperatures and knee-deep snow was the most challenging so far. The ex-High School of Glasgow pupil, who returned to the UK from the Arctic after coming third overall in the woman's race and the highest placed female Brit, said: "It was brutal and hostile. It was quite a mental battle. I arrived back to find the London Marathon on that morning and the contrast couldn't have been greater. The sun was out and the atmosphere was lovely compared to what I'd just left behind. But, without taking anything away from those runners and their achievements, I couldn't ever go back to running an ordinary road marathon - not after some of the sights I've seen."
The North Pole event bills itself as the 'World's Coolest Marathon' and is run on a drifting ice sheet, around six to 12 feet thick.