“You know about the horse crippler cactus?” asks Andrew Barnebey, my guide on the trail. I follow him to a spot where, hidden in the brush, flush to the earth, is a squat, needle-covered cactus that looks as welcoming as Hellraiser’s Pinhead. “They have these clusters of spines, or thorns,” he says. “One of the thorns is extra tall and very tough, so if a horse steps on it, it pierces the soft middle of the hoof.” Ouch.
This is one of many tidbits I learn on a guided nature walk at the Devil’s Sinkhole State Natural Area, located about 6 miles east of the remote Hill Country town of Rocksprings. Best known for its famous cave, where Mexican free-tailed bats roost and hunt nightly between May and October, the natural area is also one of the darkest places in the state for stargazing. On this nature walk, though, I discover there’s plenty to see here in daylight.
Devil’s Sinkhole State natural area
101 N. Sweeten St., Rocksprings.
830-683-2287; tpwd.texas.gov
Before the tour, I met Barnebey at the Rocksprings Visitors Center, located on the courthouse square. Every tour starts here. People can look at exhibits about the sinkhole and the bats; check out a large chunk of petrified palmwood, the official State Stone/Fossil of Texas; and read about the F5 tornado that hit the town on April 12, 1927, killing more than 80 people. There are also souvenirs to purchase, like a mug reading “Guano Happens.”
I watch the eight-minute video that explains how the sinkhole was formed and discovered. Thousands of years ago, water hollowed out a cavern, then the ceiling collapsed, creating the largest cave room in the state, with a ceiling opening the size of three football fields. Around 1870, a ranch hand named Ammon Billings came upon it and told his wife that he found the “access way to hell.” She suggested toning it down to just Devil’s Sinkhole.
The least visited of Texas’ 89 state parks and natural areas, between 3,000 and 5,000 people visit the 1,860-acre Devil’s Sinkhole State Natural Area each year. That might change with the recent acquisition of 1,200 additional acres for a 10-mile trail system. For the foreseeable future, the place remains one of only three state parks with restricted access, meaning visitors can only enter with a guide. Barnebey explains why on our walk, stopping to point out such hazards as a buzzard trap once used by ranchers, active harvester ants, and some prickly pear.
First, the area is home to four endangered species: the spot-tailed earless lizard, the golden-cheeked warbler, the Tobusch fishhook cactus, and the Devil’s Sinkhole amphipod, found only in the cave’s underground lakes.
Then there’s the sinkhole. It’s dangerous, with a 150-foot drop from the ceiling opening to the breakdown mountain, formed by the collapsed ceiling rock. What the cave residents leave behind is also a hazard. “Bat guano is the richest of all the natural fertilizers,” Barnebey says. “Flick a cigarette or something in there and who knows?”
The most important reason, he says, is the native tribe campsites on 900 acres, which are off-limits to tourists. “They’re Texas treasures,” Barnebey says. “They don’t want anyone coming out and digging for stuff.”
Designated a National Natural Landmark in 1971, the sinkhole and nearby ranchland was purchased by the state in 1985. Sixteen years after that, the nonprofit Devil’s Sinkhole Society was founded, with volunteers overseeing the guided tours. Barnebey, a retired high school teacher, has volunteered since 2002. He can give as many as four tours a day during a peak bat season.
Once the fourth largest bat colony in Texas, the bat population has declined in recent years, from 3 million to a few hundred. No one is sure why. Barnebey theorizes that the cave temperature, normally 67 degrees, could have dropped after the freeze in 2021, unsettling the bats. Other theories range from recent droughts causing a reduction in the food supply (mostly moths) to shiny aluminum benches irritating the bats.
As Barnebey talks, he directs my eyes to native grass species, including sideoats grama, the State Grass of Texas; a swirly patch he calls the “tornado plant;” and cold bear grass, which is neither a grass nor is it related to the animal. Agarita and persimmon bushes, oak and juniper trees, they’re all here. As are all kinds of animals, including 100-plus bird species, raccoons, and elk that sometimes visit from a nearby ranch.
The highlight of the tour comes at the end. I walk out on the platform and am struck by how large and deep the sinkhole is in front of me. Peering into it, a wave of vertigo hits. I step back for a moment, then work up the nerve to crane just past the railing to see how far down it goes. I carefully hold out my phone to capture it.
“Has anyone ever dropped anything in there?” I ask Barnebey.
“People are really very, very cautious,” he says. “Last year, I finally contributed a pair of my glasses.” There’s also a baby shoe down there, left by a six-month-old.
Everything about the Devil’s Sinkhole makes me feel like I’m in on a secret: the remoteness, the restricted access, the fiendish name that belies the untamed beauty, the hidden elements. Luckily, there’s always a guide willing to share every juicy detail about it.
