Inferno Triathlon

15 - 16 August 2025

A test of endurance and strength from Thun to the Schilthorn

Experience the Inferno Triathlon at close quarters. With a 5500-metre climb, this is one of the world’s toughest triathlons. A 3.1 km swim, 97 km of road biking, 30 km on a mountain bike and a 25 km mountain run await well-trained athletes. Whether you take part yourself or show your support from the side of the track, this unique experience in the heart of nature from Thun via Interlaken to the Schilthorn makes this one of the world’s most impressive competitions.

The Inferno Triathlon at a glance

  • Date: 15 - 16 August 2025

  • Location: Start in Thun / End on the Schilthorn / various transition areas along the route

  • Food/Drink: Numerous eating and drinking stalls along the route

  • Entry fees differ depending on the discipline, detailed information can be found at www.inferno.ch

Sport with a stunning scenic backdrop of the Eiger, Mönch and Jungfrau peaks

Rennvelofahrer unterweg auf einem Bergweg vor stimmungsvoller Bergkulisse

A tough race awaits Inferno Triathlon competitors, a race that has been held in the Bernese Oberland since 1998. Unlike other triathlon events, the necessary infrastructure is not provided at a central point, but the start, transition areas and finish are all in different locations. The triathlon starts in Thun, the transition areas are in Oberhofen, Grindelwald and Stechelberg, and the finish is on the Schilthorn. The half-marathon starts in Lauterbrunnen, and the athletes’ village is in Mürren, which is also the finish for the Team Trophy. Whether you take part in the triathlon yourself or cheer the athletes on from the side of the track, the Bernese Oberland’s impressive natural scenery will be your constant companion at this sporting event.

The disciplines

Läuferin erreicht mit Freude das Ziel des Inferno Triathlons auf dem Schilthorn

The triathlon begins with a 3.1 km swim in Lake Thun, followed by 97 km of road biking and 30 km on a mountain bike. It ends with a 25 km mountain run. With its 5,500-metre climb, the Inferno Triathlon is one of the world’s toughest triathlons. Alongside the actual triathlon, other less demanding disciplines are available. Competitors in the Inferno Team Trophy and Couple can take part in the triathlon in teams of two or four. The Inferno Half Marathon is a challenging 21 km mountain run up the Schilthorn. Beginners and less experienced athletes can also take part in the Mürren Fun Marathon.

Five reasons why you should attend the Inferno Triathlon

  • Sport with a stunning scenic backdrop of the Eiger, Mönch and Jungfrau peaks

  • Unique sporting experience in the heart of nature

  • Test your endurance limits

  • Different disciplines on offer, from swimming to race biking, mountain biking and mountain running

  • Friendly atmosphere

Your accommodation in Interlaken – Stay overnight with a view of the Jungfrau

Relax and unwind after this challenging sporting event in Interlaken.