Jungfrau-Marathon
Race Day Weather
Cool start — fast day potential, warming through the race, chance of rain
A cool 45°F at the start line is ideal for fast times — expect to warm up quickly once you're moving. Temperatures rising to 59°F through the course will gradually increase perceived effort in the second half. There's a chance of rain, so have a backup gear plan ready. Moderate humidity at 74% is worth noting for effort level, especially in later miles.
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Race Info
The Jungfrau-Marathon starts on the Höheweg in Interlaken, Switzerland, and finishes at the Eigergletscher station at 2,320 meters, below the north faces of the Eiger and Mönch. The 42.195-kilometer course runs flat along Lake Brienz for the first 10 kilometers before climbing through Wilderswil, Lauterbrunnen and Wengen, gaining about 1,953 meters overall. It draws roughly 4,000 entrants each September and enforces timed checkpoints at Wengen and the Wengernalp-Wixi junction to keep runners ahead of the mountain terrain.
