The Clark Fork River is 310 miles long and is the largest river, by volume, in Montana. Originally, it was inhabited by the Flathead tribe.  It was explored in 1806 by the Lewis and Clark Expedition, and was subsequently named after William Clark.

The watershed begins in Deer Lodge where it flows northwest through Missoula.  It continues into Idaho where it flows into the Pend Oreille Lake, and eventually drains into the Columbia river in Washington.  Around 200 miles of the Clark Fork river runs through Montana and we fish it all.

The Clark Fork River is notable for being the most underrated fishery in the state of Montana, if not the entire West.  Fly fishing the upper Clark Fork, southeast of Missoula, consists of shallow, meandering undercut banks, and is more of a brown trout fishery.  In contrast, the lower portion, northwest of Missoula, is more of a rainbow trout and cut-bow fishery.