Festival des 3 Forêts
Mériel, France • 13-14 Sep 2025
The Festival of the 3 Forests is a unique running event that connects the three largest forested areas in Val d’Oise, offering a 162 km course. Participants traverse diverse landscapes, including the Carnelle Forest, the Isle Adam Forest, and the Montmorency Forest, while discovering the Vexin Français Regional Nature Park and its charming villages. This festival provides ultra-trail runners with the opportunity to take on an exceptional challenge and enjoy the satisfaction of reaching the finish line after a journey through nature. Visit the organization's website for the most recent information.