Travertine Hot Springs

Travertine Hot Springs are located two miles Southeast of Bridgeport, California on several sizeable travertine terraces, overlooking views of the High Sierra mountains.^[2] Volunteers have built a series of primitive rock pools and wood-and-concrete enclosures to contain the water, and to control temperature by diverting the flow through stepped channels.^[2] The springs are located on California State Park land.^[3]

According to David Risley, a geologist with the U.S. Forest Service, the hot springs gets its name from the build-up of calcium carbonate (a form of limestone) that forms the mineral terraces. In the mid-1890s, 60 tons of travertine was mined from the site to build the interior facings of San Francisco City Hall, and other buildings.^[1]

For hundreds of years the hot mineral springs were used by local indigenous people and later, early settlers. According to archaeological records, Paleo-Indians used thermal springs in the American west for 10,000 years, based on evidence of human use and settlements. Hot springs provided warmth, healing mineral water, and cleansing.^[4] Later, the Paiute people used the hot springs.^[1]

In the early 1900s, the first wood-lined pool for dipping sheep was built; some of the wooden planks currently at the site are the original boards.^[2]

The hot mineral water emerges from several geothermal fissures in the ground at 180°F (82°C) and are cooled to 115°–156°F as they progress through the travertine terraces.^[5] Due to underground movement caused local and regional earthquakes, the temperature fluctuates.^[2]