Big Lost River Access Trail


The Big Lost River Access Trail begins outside of Mackay, Idaho and provides visitors with hiking, fishing, and wildlife viewing opportunities. This trail is about 1 mile long, one way, and open to non-motorized use only. The Big Lost River contains Brook, Rainbow, and Cutthroat Trout species. 

Please respect the adjacent private property by staying on the trail. There is typically cell service at this site.

Adventure is at Your Fingertips


Challis Field Office
721 East Main Ave Suite 8

Geographic Coordinates

43.91472222, -113.6372222


Approximately 1 mile northwest of Mackay, Idaho along the Big Lost River. Turn west off of Hwy. 93 onto Main St. in Mackay. Continue south; Main Street turns into Smelter Road and crosses the Big Lost River (there is a signed IDF&G public river access on the southeast side of the bridge). Proceed approximately 1 mile, cross the cattleguard and turn right. Follow this road approximately 2 miles to the signed day use parking area for the Big Lost River Access Trail, located on the north side of the road.


There are no fees associated with this area.