An article in the Globe on Massachusetts trails describes Stony Ledge (apparently a major venue for Mountain Day activties):
Mountain views: Roaring Brook/Stony Ledge Loop, Lanesborough
Stony Ledge is a group of rocky cliffs with views of Mount Greylock’s summit, the highest in the state (3,491 feet), and the V-shaped wedge of trees on its slopes called The Hopper. From the parking lot on Roaring Brook Road, a 20-minute drive south of Williamstown, follow the path along the right side of the brook. Cross the stream three times until you reach a point where the Roaring Brook and Stony Ledge trails split. Choose the less ardu ous Roaring Brook trail.
Climbing more than a 1,000 feet through a forest of hemlocks, spruces, yellow birches, and beeches, the trail finally reaches Sperry Road. A left on this gravel road through a campground leads to Stony Ledge. From the rocks, you can see the War Memorial atop Greylock and The Hopper’s velvety carpet of trees.
Three hours round trip; moderate to strenuous. From Williamstown, follow Route 7 south past the Route 43 junction. Look for a small wooden sign at the left-hand side of Route 7 indicating the Roaring Brook Trail. This is Roaring Brook Road. Turn left; a small parking lot is on the left