Mount Monadnock, or Grand Monadnock, is a mountain in the town of Jaffrey, New Hampshire. It is the most prominent mountain peak in southern New Hampshire and is the highest point in Cheshire County. It lies 38 miles southwest of Concord and 62 miles northwest of Boston. At 3,165 feet, Mount Monadnock is nearly 1,000 feet higher than any other mountain peak within 30 miles and rises 2,000 feet above the surrounding landscape.