Grand Lake of the Cherokees (73 sq mi/189 sq km), Mayes, Del., and Ottawa cos., extreme NE Okla., on Neosho R., in Ozark Recreation Area, 55 mi/88 km NE of Tulsa; 36°28'N 95°02'W. Max. capacity 1,537,000 acre-ft. Formed by Pensacola Dam (150 ft/46 m high), built (1940) for power generation.