mountain situated at the northern boundary of the 622-square-mile (1,611-square-kilometre) Cradle Mountain–Lake St. Clair National Park, in northwest-central Tasmania, Australia. Located on Tasmania's central plateau, its lava basalt peak rises to 5,069 feet (1,545 m). It is an arête (narrow ridge) that resembles a cradle, hence the name. Henry Hellyer, a surveyor, was reportedly the first European to scale the mountain, a feat he accomplished in 1831. The park's great beauty attracts many hikers, despite its arduous climate; it is part of the Tasmanian Wilderness UNESCO World Heritage site, designated in 1982.