Purple Valley Trails on Berlin Mountain offers roughly five miles of singletrack on the northern slopes of one of Massachusetts' tallest peaks, with the system straddling the border between Massachusetts and New York. The trails are situated on approximately 1,200 acres pieced together by Williams College, the Williamstown Rural Lands Committee, and the Berkshire Natural Resources Council.
The beginner-friendly Proof of Concept loop is a quarter-mile green trail featuring pumps and rollers—think of it as a long pump track through the woods. For intermediate riders, Learning Curves climbs nearly a mile up Berlin's eastern slopes, gaining 350 feet of elevation before connecting to 203, a descending-only trail with a solid mix of flow and tech that drops the elevation in half a mile. The Green Wave loop and the beginnings of Cirque, a blue trail that will eventually form a roughly four-mile loop around the valley, add more intermediate options.
Advanced riders can session 205, a black DH flow trail featuring mandatory doubles and gaps. Cirque currently climbs off the Green Wave loop and provides access to the top of 205. The trail system is still expanding, with more mileage planned to provide something for everyone.