XRUN Les Tertres Mystérieux is a trail race in Poland's Beskid Wyspowy, centered on Słopnice and the Mogielica massif. It guides runners into wilder, quieter terrain than a road race, featuring forest tracks, less-traveled paths, and small summits or elevated points that lend the series its name. This event is part of the XRUN series; completion awards a medal after navigating ascents, woodland stretches, and footing that can quickly become difficult in wet conditions.
The course navigates between heights connected in the race's narrative to old local legends, but the core challenge remains: traverse the tertres and arrive at the finish. Rain can create mud and make grip the primary obstacle. Post-race, participants are directed toward Dobczyce, Limanowa, and the Mogielica observation tower, offering views stretching to the Tatras, Gorce, and Beskid Sądecki. Local traditions shape the post-race recovery: cold water for weary feet in the Słopnicki stream, a peaceful stroll around Limanowa's market square and basilica, and regional dishes like kwaśnica soup or brigand-style pancakes.