British runner Nicky Spinks has spoken of the extreme challenges faced by competitors in last weekend’s Barkley Marathons – a race which no-one finished for a second successive year.

The 51-year-old breast cancer survivor was the last-woman-standing alongside fellow participant Stephanie Case in the 100-mile mountain event, widely-regarded as the world’s toughest ultramarathon.

“I’m not one to give up on anything, but I’m glad we made the decision we did. It was the right decision.”

Spinks and Case completed the first 20-mile lap together, before dropping out partway through lap two amid plummeting temperatures and appalling weather conditions.

Only 15 runners have finished the full five laps of the notorious Barkley Marathons inside the 60-hour time limit since its inception in 1986. This year saw five runners complete three laps, but none achieved four, let alone five.

The race, made famous by a 2014 Netflix documentary, saw 40 selected runners self-navigate their way around an unmarked course, tearing pages from hidden books as they went, and returning them to the enigmatic event organiser.

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Staged in Frozen Head State Park, Tennessee, USA, each lap included around 10,000ft of brutally-steep, obstacle-laden, muddy mountain ascent through thick woodland.

Nicky, an Inov-8 ambassador and record-holder for the Double Bob Graham and Double Ramsay Round, said: “The Barkley Marathons was extremely tough, in many ways. The first lap was run in really hot conditions, too hot for my liking, and then the second lap was the opposite, unbelievably cold with lots of rain.

“Together with male runners called Micheal Panhuysen and Billy Reed, we all had a quick turnaround with our support crews, and then set out as a foursome on lap number two in the dark. The weather forecast didn’t really detail just how cold it was going to be in the mountains and none of us had extreme winter kit in our race packs. It turned out to be incredibly cold and wet which, together with the darkness and fog, made for slow-going.

“When we realised we had no chance of completing lap two inside the time limit, we took an escape route back down a valley to the camp. At this point there were three of us, as Michael was behind, having decided to go slower. I’m not one to give up on anything, but I’m glad we made the decision we did. It was the right decision. Even coming back down the valley, away from the higher ground, we were still struggling with the cold. I don’t think I’ve ever felt that cold.

“We returned to camp in the early hours, though I’m not sure when exactly as the watches Laz (race organiser Gary ‘Laz Lake’ Cantrell) made us all wear didn’t tell the proper time!

The first completion of the Barkley was by Mark Williams in 1995. Winners in recent years have included John Kelly and Jared Campbell. The race is yet to see a female finisher.