There are 6 river accesses on the Bighorn that are of significance to fly fisherman. Afterbay, Three Mile, Bighorn, Mallards, and Two-Leggins, and Arapooish.
The Afterbay access and boat ramp is first access for Fly Fishing on the Bighorn River at the base of the Afterbay dam. The Afterbay dam is a smaller dam, about 60 feet, about a mile below the 600 foot tall Yellowtail Dam. This access fishes decently just 10 yards below the boat ramp. You can walk downstream from this boat ramp and access some of the Bighorn’s finest waters.
The Three-Mile access and boat ramp is the most popular access on the Bighorn River. It sits below a network of channels known as the Three-Mile islands. You can hike upstream and find many types of water ranging from small creek-like situations to the outside edge of this island where you can fish the main channel and it’s shelfs. You can also walk downstream to some decent water.
Bighorn access at the 12.5 mile of river is mostly just a boat take out. There is definitely some wadeable water, but a lack of structure makes it a little slow at certain times.
Mallards is mostly a boat take out as well, but can provide some excellent Bighorn River Fly Fishing at specific times of year. A steep bank on the access side makes much of it unwadeable until about 100 yards upstream.
Two-Leggins access and boat ramp is alightly used seasonal ramp, low trout populations at this 30th mile of the river makes wade fishing fairly futile as it is transitioning into a thriving warm water fishery with Small mouth bass.
Aarapooish is mainly a warm water fishery and the wade fishing is unknown really. Smallmouth bass abound, but fishing them while wading is a difficult feat here. There is a pond here as well at this access that is about 15 acres and has a nice Smallmouth population.

Bighorn River, Fort Smith Montana
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