| Lost River Peak | |
| Elevation Ft: | 12078 |
| Prominence Ft: | 678 |
| Parent Peak: | Mount Breitenbach |
| Location: | Custer County, Idaho, U.S. |
| Range: | Lost River Range |
| Map: | USA Idaho |
| Coordinates: | 44.0421°N -113.6547°W |
| Topo: | USGS Leatherman Peak |
| Easiest Route: | Scrambling, |
Lost River Peak, also known as Lost River Mountain, at 12078feet above sea level is the sixth-highest peak in the U.S. state of Idaho and the fifth-highest in the Lost River Range. The peak is located in Salmon-Challis National Forest in Custer County. It is 1.8miles southeast of Mount Breitenbach, its line parent.[1] [2]