One of the biggest triathlons in the world led to a surprising scientific discovery. In August 2023, we organised Noam Yaron's 3rd challenge : crossing Switzerland from East to West through the Alps by running, cycling, and swimming across the 10 most beautiful Swiss mountain lakes located on the route. A challenge of 750km and more than 13'000m of D+ was achieved in just 7 days, the main objective of which was to collect water from these 10 lakes to sequence their DNA with the help of Summit Foundation. The results produced in the laboratories of the Swiss start-up SimplexDNA are clear :  there are jellyfish in Switzerland  ! And more precisely in St. Moritz, a world's first!