a volcano in SW Alaska, in the Aleutian Range: erupted in 1912 forming the Valley of Ten Thousand Smokes, a region with numerous fumaroles; established as Katmai National Monument, 10 917 sq km (4215 sq miles), in 1918. Height: 2047 m (6716 ft). Depth of crater: 1130 m (3700 ft). Width of crater: about 4 km (2.5 miles)