Coos County is the largest and northernmost of the counties of New Hampshire. It has a land area of 1,791 sq. mi., compared to 1,058 for the State of Rhode Island. Large areas lie at an elevation of over 2,000 ft., and some of the highest and best known mountains of the northeastern United States are located in the county. Included is the famous Presidential Range, with Mt. Washington (6,288 ft.), Mt. Adams (5,798 ft.), Mt. Jefferson (5,715 ft.), Mt. Madison (5,363 ft.), Mt. Monroe (5,385 ft.), Mt. John Quincy Adams (5,450 ft.), etc.