Madison River

The Madison River begins where the Firehole and Gibbon rivers merge inside Yellowstone National Park, flows north through the Madison Valley between the Madison and Gravelly ranges, and joins the Jefferson and Gallatin at Three Forks to form the Missouri River. It is one of the most celebrated trout streams in North America — a river that defines Montana fly fishing for many who visit. Below Quake Lake, the upper Madison runs through open ranch valley as a broad, riffly freestone with consistent insect hatches and brown and rainbow trout that have made it a destination fishery for a century. Bear Trap Canyon, where the Madison cuts through the Madison Range before entering Ennis Lake, is the only whitewater section — a Class IV wilderness canyon managed by BLM that is as much about the geology and isolation as the rapids. Below Ennis Lake, the lower Madison is a tailwater that runs through the canyon above Three Forks. Lewis and Clark named the river for Secretary of State James Madison in 1805.

Bear Trap Canyon is cut through Precambrian metamorphic rock — some of the oldest exposed rock in Montana. The canyon's narrow walls of gneiss and schist contrast sharply with the broad valley upstream. The 1959 Hebgen Lake earthquake dramatically reshaped the upper river, creating Quake Lake and burying a campground.

The Madison supports one of Montana's premier wild trout populations. The upper river's thermal features from Yellowstone create unique insect hatches. Bear Trap Canyon's wilderness designation protects habitat for bighorn sheep on the canyon walls.