Alturas Lake

Alturas Lake is an alpine lake in Blaine County, Idaho, United States, in the Sawtooth Valley in the Sawtooth National Recreation Area. The lake is approximately 21 mi south of Stanley and 30 mi northwest of Ketchum. Alturas Lake can be accessed from State Highway 75 via Sawtooth National Forest road 205.

In the southern section of the Sawtooth Valley, Alturas Lake is the second largest lake in Sawtooth National Recreation Area and has easy access around its northern shore, several campgrounds, and private camps. Leah Lake and Logjam Lake are upstream of Alturas Lake.

The lake took its name from the now-defunct Alturas County, Idaho.