Lost River Peak

{{Short description|Mountain in Idaho, United States}}

{{Use mdy dates|date=January 2025}}

{{Infobox mountain

| name = Lost River Peak

| photo = Lost River Mountain.jpg

| photo_caption = South aspect

| photo_alt =

| elevation_ft = 12078

| elevation_ref =

| prominence_ft = 678

| prominence_ref = {{cite peakbagger|5154|Lost River Mountain, Idaho|January 2, 2013}}

| parent_peak = Mount Breitenbach

| location = Custer County, Idaho, U.S.

| range = Lost River Range

| map = USA Idaho

| coordinates = {{coord|44.042135|N|113.654658|W|type:mountain_region:US-ID_scale:100000|format=dms|display=inline,title}}

| range_coordinates =

| coordinates_ref =

| topo = USGS Leatherman Peak

| easiest_route = Scrambling, {{YDS|3}}

}}

Lost River Peak, also known as Lost River Mountain, at {{convert|12078|ft|m}} 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 {{convert|1.8|mi|km|abbr=on}} southeast of Mount Breitenbach, its line parent.{{cite web |title=The 100 Highest Peaks |publisher=Idaho: A Climbing Guide |url=http://www.idahoaclimbingguide.com/100%20Highest%20id149.htm |access-date=January 2, 2013}}{{cite summitpost|152086|Lost River Peak|January 2, 2013}}{{cite web |title=Idaho 12ers Home Page |publisher=Idaho Summits |url=http://idahosummits.com/over12/over12.htm |access-date=January 2, 2013}}