Middle Fork Koyukuk River

Middle Fork Koyukuk River
Location of the mouth of the Middle Fork Koyukuk River in Alaska
Location
CountryUnited States
StateAlaska
Census AreaYukonKoyukuk
Physical characteristics
SourceConfluence of Bettles and Dietrich rivers
  locationnear Wiseman, Brooks Range
  coordinates67°38′26″N 149°44′29″W / 67.64056°N 149.74139°W / 67.64056; -149.74139
  elevation1,419 ft (433 m)
MouthKoyukuk River
  coordinates
67°02′30″N 151°04′00″W / 67.04167°N 151.06667°W / 67.04167; -151.06667
  elevation
724 ft (221 m)
Length62 mi (100 km)

The Middle Fork Koyukuk River is a 62-mile (100 km) tributary of the Koyukuk River in the U.S. state of Alaska. Formed by the confluence of the Bettles and Dietrich rivers near Wiseman on the southern flank of the Brooks Range, the Middle Fork flows generally southwest to its confluence with the North Fork Koyukuk River, with which it forms the main stem of the Koyukuk.

From its starting point slightly north of Sukakpak Mountain, the river flows generally south or southwest in its upper reaches. The Dalton Highway and the TransAlaska Pipeline run roughly parallel to the river between its source and a point between Twelvemile Mountain, on the river's right, and Cathedral Mountain, on the left, south of Coldfoot. Further south, at Tramway Bar, the river turns generally west to its confluence with the North Fork Koyukuk River.