It was six o’clock on Friday morning, at least 15 minutes before dawn over Texas’ capital city, and scores of vehicles had already crowded into the parking lot at Barton Springs Pool, a few miles — and in some ways, an entire world — from the lighted skyscrapers of downtown.
Jeremy Baumann, a local health care worker, had already been in the water for an hour, getting in his daily laps. As the city settled in for another day of triple-digit heat, a devoted procession that would reach several thousand by the evening headed toward the three-acre, spring-fed pool: families hauling plastic floaties, workers briefly escaping from offices, longtime friends and neighbors meeting poolside as much to socialize as to swim.
When Austinites talk about Barton Springs, they do so in almost spiritual terms. “It’s very much a sacred place,” said Kim McKnight, manager of historic preservation and tourism for the city’s Parks and Recreation Department. “I recognize not everybody goes there, but for those who do they can’t imagine life without it.”
A part of the Austin landscape since the early 20th century, the pool is so beloved that residents resorted to near rebellion to save it from developers in the 1990s. Marriages and funerals are regularly held on its grassy banks. The city brags on its website that the actor Robert Redford learned to swim there at the age of 5 when he was visiting family in Austin.
Texas was gripped early on with a powerful heat wave that has now spread across the South and Southwest, leaving large parts of the country to battle perilously high temperatures. Over 93 million people were under excessive heat warnings or advisories for the coming weekend, as dangerous heat spanned the country from the West Coast to the Gulf Coast and threatened to break records in California, Arizona and elsewhere.
In Austin, where temperatures as high as 107 were forecast to persist through much of the coming week, the cars kept pulling into the parking lot at the springs, where the water temperature — winter or summer — averages a comfortable 68 to 71 degrees.
Waiting in the long lines at midday to enter Barton Springs Pool — admission is $5 a person for adult residents — is sometimes the difficult part. Cassidy Stillwell, a lifeguard and facilities manager, said those waiting in line were at times subjected to heat stress. Patrons are advised to arrive with sunblock and water.
Fed from four springs pouring in from the Edwards Aquifer, the pool, with its natural bottom, concrete sides and decking, and a wide expanse of trees and lawns, resembles a lake or river more than a pool — a natural oasis in the middle of a city that is one of the fastest growing in the United States.
“We love it, especially being so hot outside,” said Cedric Atwood of Dallas, who woke up with his family at about 4 a.m. and set out for the springs. Mr. Atwood, his wife, daughter and grandson arrived about four hours later with an armload of pool toys and plans to stay for most of the day before heading back in the midafternoon.
Many of those gathered along the banks shared memories of the pool dating back to their childhood.
Lynn Cooksey, the 88-year-old wife of the former mayor Frank Cooksey, said she first starting coming to Barton Springs when she was a freshman at the University of Texas in 1953. On Friday, she was wearing a flowered bathing cap and sitting alongside her close friend, Anne Wheat, whose parents first brought her to the pool shortly after she was born in 1957. Ms. Wheat’s parents met on a blind date at the pool in the late 1940s.
The two women planned to swim, but, like many of the pool’s regulars, they had also come to absorb the tranquillity that seems to radiate across the surrounding landscape of Zilker Metropolitan Park.
“It’s such a beautiful natural setting,” said Ms. Cooksey, who gets free admittance with her pass for those 80 and older.
The pool is home to a variety of fish and turtles, and is also a federally protected habitat for the endangered Barton Springs salamander. Many of those who came on Friday brought goggles and flippers to plumb the pool’s 18-foot depths, hoping for a glimpse of the invisible life below.
Patricia Bobeck, a hydrogeologist who lives about three miles away, said she often donned a snorkel and swam from one end of the pool to the other.
“It’s fascinating,” she said. “It’s like swimming in an aquarium. It’s like being a guest where the fish live.”