This Texas cave wasn’t carved by dripping water but by an ancient river

It’s 90 minutes from Austin

Longhorn Cavern State Park sits in Burnet County, about 90 minutes northwest of Austin, on 645 acres of rough Hill Country terrain along Backbone Ridge.

The cavern earned National Natural Landmark status in 1971, and the park’s administration building became a Recorded Texas Historic Landmark in 1989.

You can walk the trails and explore the grounds for free.

The only thing that costs money is going underground, and that part is worth every dollar. What you find 130 feet below the surface took half a billion years to build.

Half a billion years of water shaped these walls

Most caves form from water dripping down through rock. Not this one.

An ancient underground river carved Longhorn Cavern through 500-million-year-old Ellenburger Limestone, dissolving and cutting the stone instead of slowly wearing it away.

That left smooth, sculpted walls and passages instead of the rough, craggy surfaces you see in typical drip caves. The whole system runs about 11 miles, though only a section of it is open to the public.

The forces behind it go back even further, to the Llano Uplift 280 to 300 million years ago, when the shifting earth cracked the limestone and gave the water a way in.

52 stone steps take you 130 feet underground

You start by walking down 52 wide, well-lit stone steps to reach the cavern entrance, 130 feet below the surface.

Once you’re inside, the temperature sits at 68 degrees year-round, no matter how hot or cold it is above. The path follows a dried ancient riverbed and covers about 1.1 miles round trip.

Most of it is paved and level, though you’ll need to duck in a few spots where the ceiling drops to about four feet four inches.

At one point during most tours, the guides turn off every light and let you stand in total darkness.

The Queen’s Throne and the Hall of Diamonds

The guided Walking Tour takes about 90 minutes at a slow pace, and you pass through rooms that each have their own look.

The Queen’s Throne is a large flowstone mass and one of the biggest travertine deposits in the cave. The Indian Council Room is the largest chamber, with chert, a flint-like rock, lining the walls.

Crystal City glitters with calcite crystals.

The Hall of Marble has smooth dolomite walls that look like polished white stone, and the Hall of Diamonds is one of the largest crystal rooms in any Texas cave.

Crawl through mud on the Wild Cave Tour

If the Walking Tour feels too easy, the Wild Cave Tour takes you into the undeveloped lower level for about three hours.

You crawl through tight passages, wade through water, and push through mud on your hands and knees. The park gives you helmets, headlamps, knee pads, and gloves.

You need to be at least 8 years old, and you can’t exceed 52 inches in girth at the shoulders or hips. Groups run small, usually about eight people, with an experienced cave guide leading the way.

Carry a lantern before the lights come on

Once each weekend morning at 9:30 a.m., the park runs a 60-minute tour before they flip on the regular cavern lights.

You carry a lantern and a blacklight flashlight through the dark. The blacklight reveals glowing features of living rock that you can’t see on the standard tour.

The path is mostly level but dimly lit, so you move carefully and see the same formations in a completely different way.

If you’ve already done the Walking Tour, this one changes everything you thought you knew about the cave.

The CCC cleared 3,000 dump trucks of debris by hand

Civilian Conservation Corps Company 854 developed the park between 1934 and 1942.

Those young men hauled out the equivalent of more than 3,000 dump trucks’ worth of debris from the cavern using nothing but hand tools and wheelbarrows.

Every structure used native stone and wood in the National Park Service Rustic style, known as “parkitecture,” so the buildings blend into the landscape.

They also built stone staircases, walkways, an observation tower, residences, and pavilions. A CCC exhibit tells its story from the Great Depression.

Spot a fake Bavarian castle from the tower

The CCC-built observation tower stands near the picnic area and gives you a 360-degree view of the surrounding Hill Country.

From the top, you can see rolling hills, open farmland, and the Falkenstein Castle, a private home somebody built to look like a medieval Bavarian castle.

The tower itself is a three-story stone structure with easy spiral steps to the top.

It’s one of the best-preserved examples of CCC architecture in the entire Texas state park system, and the climb takes just a couple of minutes.

Walk among endangered birds on Backbone Ridge

The park has more than a mile of well-marked nature trails cutting through oak and juniper woodlands.

The main loop runs about 1.1 miles and takes 20 to 30 minutes to walk.

Keep your eyes open for the endangered golden-cheeked warbler and the black-capped vireo, both of which live in these woods.

You might also spot jackrabbits, roadrunners, and butterflies along the way. If you brought your dog, leashed pets are welcome on all the above-ground trails.

Kids can crack open geodes above ground

Above ground, kids and adults can try gemstone mining at the park’s sluice station. You can also crack open geodes and see what crystals are hiding inside.

Shaded picnic areas with tables spread across the grounds, so you can bring lunch and make a day of it.

Strollers can go inside the cavern, though the park recommends ones with sturdy pneumatic tires for the uneven surfaces.

If you have little ones, children under 4 get into the Walking Tour for free.

Pair it with Inks Lake, six miles up the road

Inks Lake State Park sits just six miles north on Park Road 4, and it fills every gap Longhorn Cavern doesn’t cover.

You can camp, swim, fish, kayak, and hike nine miles of trails there.

Longhorn Cavern is day-use only with no camping, so Inks Lake is the closest campground option. A lot of people combine both parks into one day trip or a weekend from Austin.

Even the road that connects them, Park Road 4, was built by the CCC in the 1930s.

The only river-carved show cave in Texas

More than 70,000 people visit Longhorn Cavern every year. It’s one of just eight show caves in Texas and the only one formed mainly by an underground river.

The temperature stays comfortable in every season, so it works as a cool escape in summer and a warm one in winter. Tour guides here have a reputation for being funny, sharp, and genuinely excited about the cave’s story.

Between the rare geology, Depression-era history, and everything you can do above ground, few state parks in Texas pack this much into one visit.

Explore Longhorn Cavern State Park in Texas

You’ll find Longhorn Cavern State Park at 6211 Park Road 4 South, Burnet, Texas. The park is open daily except on Dec. 25.

Weekday walking tours run every hour from 11 a.m. to 3 p.m., and weekend tours go from 10 a.m. to 4 p.m. Adults pay $24 and up, kids ages 4 to 11 start at $17, and children under 4 get in free.

The Wild Cave Tour starts at $110. Parking and access to the grounds cost nothing, and you don’t need reservations for the Walking Tour.

Just show up about an hour early to grab a spot.

This article was created with AI assistance and human editing.

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