Conquer 40 miles of rugged Appalachian terrain.

The Berkshire 40 XCM is a non-championship mountain bike marathon taking place on August 31, 2025, in Cheshire, Massachusetts. Set in the Berkshire Mountains, this endurance event challenges riders with a demanding route designed for seasoned cyclists who seek a true test of stamina and skill. Traverse technical singletrack trails, forest paths, and rocky outcrops while enjoying the natural beauty and excitement of one of New England’s top mountain biking destinations.

Challenging course featuring technical singletrack, forest trails, and rocky sections, utilizing the rugged terrain of the Berkshire Mountains and Thunder Mountain Bike Park.

• Hosted at Thunder Mountain Bike Park, renowned for steep descents and flow trails
• Non-championship endurance event in the Berkshire Mountains
• Part of the Race Day XC series, a staple in New England endurance racing
• Presented by Rotation Engineering and Specialized