The 50-mile stretch of the Madison River from Quake Lake [1] (near Yellowstone National Park) north to Ennis [2] is an almost continuous riffle, and trout are eager to grab passing morsels. The Madison is also the state’s most trout-dense river. This makes for good fishing for beginning fly anglers, but it also means the river can get crowded.
The first 30 miles of the Madison (from Quake Lake to Varney Bridge) is a catch-and-release area, with no live bait permitted.
The state maintains several fishing-access sites on the Madison River near Ennis.
Ennis FAS is on Highway 287 just south of Ennis; Burnt Tree Hole is one mile west of Ennis on Highway 287, then two miles south on the county road; Eight Mile Fork is four miles down the same county road; Varney Bridge is another six miles down the road. All of these spots except Ennis have informal no-fee camping sites; there’s a small fee to camp at Ennis.
To reach Valley Garden FAS, turn north from Highway 287 onto the county road 0.25 mile south of town and travel two miles. McAtee Bridge, 18 miles south of Ennis, also provides access to the Madison.
Links:
[1] http://www.moon.com/destinations/montana/the-missouri-headwaters-and-south-central-montana/three-forks-and-the-madison-river-valley/quake-lake-and-h
[2] http://www.moon.com/destinations/montana/the-missouri-headwaters-and-south-central-montana/three-forks-and-the-madison-river-valley/ennis