Gary Connell, 34, and wife Rachel Hibbert, 37, started the three-month route from the lighthouse at Cabo Higuer on the Atlantic Coast, in June, before finishing up at Cap de Creus on the Mediterranean Coast in September.

Gary – who worked at Faslane for 16 years – took a career break from his work as a nuclear engineer with AMEC along with his wife Rachel, an employee at Specsavers, to complete the challenge in aid of St Margaret’s Hospice in Clydebank.

Gary said: “The hospice is a charity close to my heart. My grandmother passed away there in 1996 and Rachel also has a friend currently residing in the hospice.” Gary said the route meandered for more than 840km with a total ascent of 39,000m – the equivalent of climbing Ben Lomond 40 times.

“The trip had its challenges including carrying provisions, such as water and food, for up to four days at a time,” he said. “It is not unusual for the temperature to range from minus 15 (even in summer) to over 35 degrees and for the mountains to have regular thunderstorms. Walking 10 hours a day with little opportunity to buy food meant that I lost more than three stones in weight. We also had to be careful of the wildlife as the area was home to lots of snakes, wild boars, and even bears and wolves.

“At one point we had to take a detour to find a cobbler after four weeks because I had worn completely through the soles of my boots.” He added: “Despite the challenges it was a great experience. The accomplishment of completing such a challenge is rewarding, especially because we manage to exceed our three-month time target and raise more than £3,000 for the hospice.”