On Alaska Peninsula, in Katmai National Monument, heads in glacial lake on Mount Mageik and flows NW through Valley of Ten Thousand Smokes to Ukak River, 18 mi. NW of Mount Katmai, Aleutian Range
Named in 1917 by R. F. Griggs, National Geographic Society; suggested by Lethe, the "river of forgetfulness" in the Hades of Greek mythology.
Baked Mountain, Mount Cerberus, Mount Ikagluik, Mount Katolinat, Mount La Gorce, Mount Mageik,
Mountain Ranges:Rivers:River Lethe, Savonoski River, Ukak River,
Streams:Ikagluik Creek, Knife Creek, Margot Creek, Windy Creek,
Valleys: