Hospital workers who scaled 17,000ft of Mount Everest in the name of medical research have returned to work at the Royal Free.

Staff members returned to the hospital, in Pond Street, Hampstead, having climbed part of the highest mountain in the world for a ground-breaking research project, made possible by a grant of £100,000 from the Royal Free Charity.

The six walkers, whittled down from nearly 100 applicants, took part in daily oxygen level, blood pressure and blood tests for the project, which could advance the treatment of patients with low levels of oxygen in intensive care.

Jennifer Morris, a pharmacy technician of Chalk Farm, said: “It was the best thing I have ever done. Everest really is the most beautiful place on earth. I’m over the moon, but glad to be back with friends and family now.”

The six staff members had never met prior to being selected to take part in the trek.

But Breda Athan, a senior matron, said: “We all gelled together. I had a personal phobia of suspension bridges, of which there were around eight on the whole trip – but we all rallied around one another and supported each other the whole way.”

The group has raised £2,000 so far but can still be sponsored, with all proceeds going to the Royal Free Charity for further pioneering research. Visit www.justgiving.com/XtremeEverest2