According to the history on the Austin parks site:
"Within Zilker Park's 358 acres, lies one of the crown jewels of Austin, Barton Springs Pool. Three acres in size, the pool is fed from under ground springs and is on average 68 degrees year round. Over the years, Barton Springs Pool has drawn people from all walks of life, from legislators who have concocted state laws there to free-spirited topless sunbathers who turned heads in the seventies. Even Robert Redford learned to swim at the pool when he was five years old while visiting his mother's relative in Austin. Today, Barton Springs still attracts a diverse crowd of people." - Barton Springs Pool
We decided not to venture into the pool since we had Max along and the water is a very chilly 68 degrees. No one had a swimming suit along either. But the kids insisted on 'wading' in the creek that the springs spills over into where lots of folks were hanging out and enjoying the lovely early spring sunshine.
Well, wading turned into full out swimming as you can see ...
That's Laz in the red shirt, and Lily behind him. The water was COLD! Seb in the foreground
Lazarus is really not drowning, we promise - though his sister would like to help him I'm sure
A toothless, happy 7 year old