West Suffield Mountain, est. 710 feet (220 m), is a traprock mountain ridge located between the Berkshires and the Connecticut River Valley in north-central Connecticut. It is part of the narrow, linear Metacomet Ridge that extends from Long Island Sound near New Haven, Connecticut, north through the Connecticut River Valley of Massachusetts to the Vermont border. West Suffield Mountain is known for its scenic ledges and woodlands, unique microclimate ecosystems, and rare plant communities. It is traversed by the 51-mile (82 km) Metacomet Trail, and the 110-mile (180 km) Metacomet-Monadnock Trail begins at the northern foot of West Suffield Mountain.

Peak Mountain, also called Copper Mountain, est. 730 feet (220 m), is a traprock mountain located in East Granby, Connecticut, 6 miles (10 km) south of the Massachusetts border and 6 miles west of the Connecticut River. It is part of the narrow, linear Metacomet Ridge that extends from Long Island Sound near New Haven, Connecticut, north through the Connecticut River Valley of Massachusetts to the Vermont border. Peak Mountain is known for its expansive views from 200 feet (61 m) high cliffs overlooking the historic Old Newgate Prison, Congamond Lake, and the Salmon Brook Valley of north-central Connecticut. The mountain is also known for its microclimate ecosystems, rare plant communities, and as a seasonal raptor migration path. It is traversed by the 51-mile (82 km) Metacomet Trail.