The treasure of Austin, the capital of Texas.
The beautiful natural spring is set against the skyline of skyscrapers.
A public swimming pool located less than a 10-minute drive from the Texas State Capitol.
It is a place beloved by the public, but also the subject of much controversy.
Although not strictly included in the hot springs that this blog specializes in, I cannot resist introducing it.
The pool is located in the Zilker Metropolitan Park, which was donated to the city of Austin in 1917 and maintained during the Great Depression.
A $5.00 parking fee applies on weekends, holidays and special events.
For non-citizens, daily admission for ages 18-61 was $9.00 (except for winter).
However, every morning from 5 to 8 a.m. is "Swim at Your Own Risk," which is free of charge but unsupervised.
In the 1920s, the city dammed the spring and developed it into a pool.
Today's bath house was constructed in 1947 and overlooks the pool.
The gender-separated changing rooms were also rich in formative beauty that might have historical and intellectual value.
The long and narrow Barton Springs Pool is 900 feet long.
It is approximately 18 feet deep at its deepest point.
The water temp is around 70 degrees F throughout the year.
As I swam, I could feel that the temperature differed slightly from place to place.
Upstream was Barton Creek, which was dammed so that river water would not normally flow into the pool.
The source, Main Spring, is located just around the center is one of the springs in the Edwards Aquifer, an area of naturally flowing groundwater.
Because a kind of salamanders here are listed as an endangered species, there has been much discussion about protecting them.
In the past, the water was disinfected with chlorine and the algae in the pool was regularly washed away with a strong stream of water, resulting in the surprisingly clear color of the water.
It was believed that this had a negative impact on the salamander ecosystem, and the park is now operated in a more naturalistic manner.
In fact, water in the pool had a dark green appearance, partly due to contamination of the Edwards Aquifer caused by the urbanization of the surrounding area.
Eliza Spring, a smaller spring adjacent to Main Spring, has been maintained in a distinctive amphitheater shape since the early 1900s.
Today, it is off-limits to people due to the salamander's native habitat and can only be viewed through the fences.
Related hot springs
San Antonio, not far from Austin, had a sulfur spring with 104 degrees F.
That was until 2013, when the source was buried, and the historic spa hotel has been preserved as a relic.