Barton Springs Pool is a recreational outdoor swimming pool in Austin, Texas, that is filled entirely by natural springs connected to the Edwards Aquifer. Located in Zilker Park, the pool exists within the channel of Barton Creek and uses water from Main Barton Spring, the fourth-largest spring in Texas. The pool is a popular venue for year-round swimming, as its temperature hovers between about 68 °F (20 °C) and 74 °F (23 °C) year-round.[1][2][3][4] The pool's grassy hills are lined with mature shade trees.
^"Water Quality Records"(PDF). Water-Data Report 2007, 08155500 Barton Springs at Austin, TX. U.S. Department of the Interior, U.S. Geological Survey. 2007. p. 4. Archived(PDF) from the original on 9 September 2008. Retrieved 2008-08-19.