EcoTrail Paris 122km — marketed as the Trail 120km — is one of Europe's flattest ultra-trail distances, running point-to-point from the Château de Rambouillet through the forests and châteaux of the Chevreuse Valley to finish at the foot of the Eiffel Tower on Paris's Pont d'Iéna. With just 2,000m of elevation gain over 122.2km and 83.4% flat terrain, it ranks as the 24th flattest course of 390 European ultra trails in the DTR database — yet a 30% DNF rate in its 2026 inaugural edition signals the distance demands respect.
Launched in 2026 as a new flagship distance for the Salomon EcoTrail Paris — an event founded in 2008 that draws 18,500 participants across all distances — the 120km sells out rapidly. The start is at the royal Château de Rambouillet, reached by Transilien train from Paris, with CDG and Orly airports under one hour away; no car is needed. A UTMB qualifier awarding 20K, 50K, and 100K Running Stones, capped at 2,500 entrants, with a 21h15 cutoff.