Purgatory Chasm State Reservation is a state-owned geologic preserve and public recreation area located off Route 146 in the town of Sutton, Massachusetts. The state park is notable for its .25-mile-long (400 m), 70-foot-deep (21 m) chasm of granite bedrock with abrupt precipices and boulder caves where ice lingers into the early summer. It is managed by the Massachusetts Department of Conservation and Recreation.