Mountrail -- U.S. County in North Dakota Population (2000): 6631 Housing Units (2000): 3438 Land area (2000): 1823.932974 sq. miles (4723.964515 sq. km) Water area (2000): 117.145277 sq. miles (303.404862 sq. km) Total area (2000): 1941.078251 sq. miles (5027.369377 sq. km) Located within: North Dakota (ND), FIPS 38 Location: 48.204135 N, 102.342666 W Headwords: Mountrail Mountrail, ND Mountrail County Mountrail County, ND