Olympic Hot Springs, Natural hot springs in Olympic National Park, Washington, United States.

Olympic Hot Springs is a group of 21 seeps near Boulder Creek, a tributary of the Elwha River, in Olympic National Park, Washington. Temperatures range from tepid to 138 °F (59 °C). The pools average about one foot deep, and some were made deeper by rocks placed to block the spring water's exit. A photograph shows a steaming pool in a rocky depression ringed by pale rounded stones, its water greenish where shallow and dark blue where deeper, with green vegetation at one edge.

The Klallam Tribe used the springs for vision quests for centuries before Andrew Jacobsen, guided by a Klallam friend, became the first person of European descent to reach them in 1892. After their rediscovery in 1907, a trail was blazed and a resort built on the site. The resort operated until 1966, when its lease with the National Park Service expired and the buildings were removed.

The Klallam Tribe used the springs for centuries as a place for vision quests. A sign at the trailhead notes that nudity is commonplace at the primitive pools and is not condoned by Olympic National Park. The springs lie on a fault, and geologists say they are uncertain of the mechanism that produces them.

The road now ends at the Madison Falls Trailhead, so reaching the Appleton Pass trailhead adds 8 miles (13 km) of hiking; from there the springs are about 2.5 miles (4 km) up the Appleton Pass Trail. Pools average around one foot deep, with mud and rock bottoms, and a trailhead sign warns that summer water is stagnant and may carry infectious bacteria, so boil or treat drinking water. Camping and fires are prohibited near the pools.

The springs rise along a fault, not through sedimentary rock: geologists believe breaks in the rock let surface water be heated and driven back up from the hot interior of the Earth, though they are uncertain of the exact mechanism. The pools average about one foot deep, and some were made deeper by rocks placed to block the spring water's exit.