Description
South Fork Fortymile River is located heads at junction of Mosquito and Dennison Forks, flows N to join North Fork to form Fortymile River, 42 mi. SW of Eagle, Yukon-Tanana High.
History
Named by prospectors and reported i1896 by Spurr (1898, pl. 38), U.S. Geological Survey (USGS). This name was probably in use as early as 1886.