Redoubt Volcano, or Mount Redoubt (Dena'ina: Bentuggezh K’enulgheli), is an active stratovolcano in the largely volcanic Aleutian Range of the U.S. state of Alaska. Located at the head of the Chigmit Mountains subrange in Lake Clark National Park and Preserve, the mountain is just west of Cook Inlet, in the Kenai Peninsula Borough about 110 miles (180 km) southwest of Anchorage. At 10,197 feet (3,108 m), in just over 5 miles (8.0 km) Mount Redoubt attains 9,150 feet (2,790 m) of prominence over its surrounding terrain. It is the highest summit in the Aleutian Range. In 1976, Redoubt Volcano was designated as a National Natural Landmark by the National Park Service.
Active for millennia, Mount Redoubt has erupted four times since it was first observed: in 1902, 1966, 1989 and 2009, with two questionable eruptions in 1881 and 1933. The eruption in 1989 spewed volcanic ash to a height of 45,000 ft (13,700 m). It caught KLM Flight 867, a Boeing 747 aircraft, in its plume. After the plane descended 13,000 feet, the pilots restarted the engines and landed the plane safely at Anchorage. The ash blanketed an area of about 7,700 mi (20,000 km). The 1989 eruption is also notable for being the first ever volcanic eruption to be successfully predicted by the method of long-period seismic events developed by Swiss/American volcanologist Bernard Chouet. As of 2018, the US Geological Survey rated Mount Redoubt a "very high threat" to people and infrastructure.
