Conclusion. An adventure race in Costa Rica is featured.

Simon and Turbo train with expert bike racers and locals in the Alps before taking on the terrifying descents and harrowing switchbacks of the hardest mountain bike marathon in Europe: the 137-mile Salzkammergut race in Austria.

Adventure races take place in Costa Rica.

The 100 mile Yukon Arctic Ultra is possibly the coldest and toughest in the world. Racers battle the elements on skis and bikes, risking frostbite and navigation issues.

100km single-day race in some the most scenic areas of northern Mongolia. Our friends from last year’s Kenya return to compete with Simon and Turbo. The race itself is one of a kind and incredibly challenging. Epic in scope and the biggest, longest ultra we have tackled to date.

Simon and Turbo train with local experts and some of the UK’s top mountain runners before taking on the historic Ramsay Round in Scotland, a 56-mile race in which they attempt to summit 24 of the country’s highest peaks. In less than 24 hours. With no sleep and no support.

Hoping to redeem themselves after a disappointing upset in Hawaii, Turbo and Simon take on a five-day, eleven-city stand-up paddleboarding race through the picture-perfect canals of northern Holland. But redemption comes at a price: sweat and pain.

At the Great River Amazon Raft Race, Simon and Turbo pair with an inexperienced married couple to race 112 miles down a remote section of the mighty Amazon River. In 3 days. On a raft they built themselves. If they want to finish in one of the top spots, there’s a lot to learn, and quickly.

The guys attempt a 353-mile bike race through the California deserts.

In the Copper Canyons of northern Mexico is a remote and wild terrain where the CB Ultra race is held. This 75km race was featured in the book 'Born to Run' and is considered to be very special among ultra runners.

A 75 kilometer race through Mexico's Copper Canyons.