Purgatory Chasm State Reservation 
198 Purgatory Rd
Sutton, MA 01590
508-234-3733
http://www.mass.gov/eea/agencies/dcr/massparks/region-central/purgatory-chasm-state-reservation.html
State Park: Birding, Hike, Picnic, Walk
Runs for a quarter of a mile between granite walls rising as high as 70 feet. Popular with picnickers and rock-climbers alike, the Chasm is believed to have its origin in the sudden release of dammed-up glacial meltwater near the end of the last Ice Age, approximately 14,000 years ago.