Barton Springs Pool

Barton Springs Pool is a recreational outdoor swimming pool that is filled entirely with water from nearby natural springs. It is located on the grounds of Zilker Park in Austin, Texas. The pool exists within the channel of Barton Creek and utilizes water from Main Barton Spring, the fourth largest spring in Texas. The pool is a popular venue for year-round swimming, as its temperature maintains as stable 68 °F (20 °C) in the winter and summer.

Long before Barton Springs Pool was built, the springs were considered sacred and were used for purification rituals by the Tonkawa Native American tribe who inhabited the area. Spanish explorers first found the springs in the 17th century, and around 1730 erected temporary missions at the site (later moving to San Antonio).

In 1837, soon after incorporation of the city of Austin, William ("Uncle Billy") Barton, the springs' namesake, settled the area. Barton named the three separate springs after his three daughters: Parthenia, Eliza, and Zenobia. He, and subsequent owners of the property, recognized its value as a tourist attraction, and promoted it vigorously, thus leading to the swimming hole's lasting popularity.

The last private owner of the property, Andrew Jackson Zilker, deeded it to Austin in 1918. During the 1920s, the city undertook a construction project to create a larger swimming area by damming the springs and building sidewalks. The bathhouse was constructed in the 1940s and modeled after the design of the bathhouse at Deep Eddy Pool.

The pool is usually open to the public from 5:00am to 10:00pm, Friday through Wednesday. During this time, the floodgates on the pool's dam are closed, and Main Barton Spring fills the pool to a maximum depth of more than 18 feet. At the upper end of the pool, another dam prevents surface water from Barton Creek from entering the pool by diverting it through a tunnel under the sidewalks.

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