It is part of the narrow, linear Metacomet Ridge that extends from Long Island Sound north through the Connecticut River Valley of Massachusetts to the Vermont border. The Metacomet Ridge extends west and south from Sleeping Giant as Rocky Top and West Rock Ridge. The west side of Sleeping Giant drains into the Mill River thence to New Haven Harbor and Long Island Sound; the east side into the Quinnipiac River, thence to New Haven Harbor and Long Island Sound.