The Middle Fork Trail #4001 is a 78-mile hiking and stock trail that begins at the Middle Fork Transfer Camp & Trailhead near Boundary Creek, offering access into the Frank Church-River of No Return Wilderness alongside the Middle Fork Salmon River.

The trailhead provides toilet facilities, stock holding facilities, a loading ramp, and long-term parking for boaters and hikers.

Users should check current trail condition reports before attempting the hike, as portions may be flooded by high water in spring and the trail experiences rockfall and downed trees; wilderness regulations and Leave No Trace ethics are mandatory.