Main Boulder Road Fishing Access Site provides public access to the Boulder River south of Big Timber, offering primitive camping and picnic facilities.

The site serves as a key access point for wade fishing on the lower Boulder River, though anglers should be prepared for challenging terrain with large boulders and slippery rocks; wading staffs are recommended.

Access is via the Main Boulder Road (FAS 298), a paved state secondary route that requires navigation through mountainous terrain.