A physiotherapist at the Royal Free Hospital is to run, hike and cycle the entire length of the “Iron Curtain” – with a little help from renowned explorer Sir Ranulph Fiennes and celebrity travellers Ben Fogle and Charley Boorman.

Justine Gosling, 30, is set to travel a gruelling 5,000 miles today (Thursday) through 16 countries as she traces the boundary that divided Western Europe from the old Soviet Union between 1945 and the end of the Cold War in 1991.

Ms Gosling, of Lisburne Road, Hampstead, devised the journey to enter the Cordon Rouge Club competition, for which would-be explorers pitch proposals for adventures, and the winning idea becomes a reality.

She is taking on the unique challenge to raise money for charity.

She said: “I entered on a whim. It was this silly little fantasy.

“But during a meeting at work, I got a message telling me I had won. I almost fell off my chair, and my first thought was, ‘My God, what have I committed to?’

“I’m reasonably fit, but I’ve never run further than a half-marathon or swum more than 5km before, so it was a daunting prospect, but also too amazing an opportunity to turn down.”

Part of the four-month expedition will see Ms Gosling walk the entire length of Finland. It is thought she will be the first person to accomplish the feat.

In preparation, she has been running half-marathons, walking for miles around London and doing strength and conditioning training.

She said: “I’m really excited and trying not to let nerves set in.

“I’m realistic. I know it’s going to be tough and there are going to be difficult times. But I will complete this. It’s not going to be pretty, it’s not going to be fast, but I will do it.”

She is being mentored by members of the Cordon Rouge Club, including legendary explorer Sir Ranulph, travel writer Mr Boorman, and adventurer Ben Fogle.

Former Hampstead schoolboy Mr Fogle said: “We were particularly inspired by Justine’s expedition due to its unique story.”

Through her endeavours, Ms Gosling hopes to raise money for two charities close to her heart – Walking with the Wounded, which provides re-education and training for wounded service personnel, and Hope and Homes for Children, which works to bring children living in orphanages back to their families.

To donate to Justine’s causes visit: uk.virginmoneygiving.com/JustineGosling.