Idaho

Kirkham Hot Springs

If you have time to kill around Boise, or are on a trip to explore the Sawtooth Wilderness, stop by Kirkham hot springs. This natural hot spring is undeveloped and right alongside a river. It features a small hot sping waterfall and multiple bathing pools. For being natural, it is very clean.

There is a national forest campground immediately next to the springs you can use to spend the night and go star watching from the pools. The springs are right off a mountain highway, but you can't see or hear it from the springs. However, its easy accesibility does make it a bit more crowded during peak seasons.