Lake Crescent is a deep lake located entirely within Olympic National Park in Clallam County, Washington, United States, approximately west of Port Angeles on U.S. Route 101 and nearby to the small community of Piedmont. At an official maximum depth of it is officially the second deepest lake in Washington (after Lake Chelan). A lake-wide bathymetric survey was performed from 2013 to 2014 by Eian Ray and Jeff Engea and the results of this survey showed the maximum depth as being 596 feet. Using GIS statistical analysis, this survey also showed the lake contains approximately 0.5 cubic miles of fresh water. Lake Crescent is known for its brilliant blue waters and exceptional clarity, caused by a lack of nitrogen in the water which inhibits the growth of algae. It is located in a popular recreational area that is home to several trails, including the Spruce Railroad Trail, Pyramid Mountain trail, and the Barnes Creek trail to Marymere Falls. The Spruce Railroad Trail follows the grade of what was once the tracks of a logging railroad along the shores of the lake. Following this trail on the north side of the lake, one can find the entrance to an old railroad tunnel as well as "Devils Punch Bowl", a popular swimming and diving area. Origins The lake was formed when glaciers carved out deep valleys during the last Ice Age. Initially, the Lake Crescent valley drained into the Indian Creek valley and then into Elwha River. Anadromous fish such as steelhead and coastal cutthroat trout migrated into the valley from lower waters. Approximately 8,000 years ago, a great landslide from one of the Olympic Mountains dammed Indian Creek, and the deep valley filled with water. Many geologists believe that Lake Crescent and nearby Lake Sutherland formed at the same time, but became separated by the landslide. This theory is supported by Klallum tribe legend which tells a story of Mount Storm King being angered by warring tribes and throwing a boulder to cut Lake Sutherland in two, resulting in Lake Crescent. The results of the landslide are easily visible from the summit of Pyramid Mountain. Eventually, the water found an alternative route out of the valley, spilling into the Lyre River, over the Lyre River Falls, and out to the Strait of Juan de Fuca. Ecology The anadromous fish populations in the lake became landlocked, because those fish could not ascend