Ironman Switzerland Thun, is a triathlon nestled in the heart of the Alps, promising an unforgettable experience for athletes and spectators alike! Swim (3.8 km): Dive into the adventure at the renovated lido as you embark on a one-loop, 3.8 km swim in the crystal-clear waters of Lake Thun. The majestic Alps surround you, creating a picturesque backdrop for a swim that is as challenging as it is awe-inspiring. With an average water temperature of 66°F/19°C, the pristine lake offers a ...