What if I told you there’s a whole other world hidden beneath your feet in Texas?
A world filled with twisting tunnels, ancient rock formations, and stories that stretch back millions of years.
Sounds like something out of a movie, right?
Well, you don’t need a treasure map or a secret code to find it—just a quick trip to Georgetown, Texas will do the trick.
Discovered completely by accident (more on this later), this underground gem is one of Texas’ coolest natural wonders.
Keep reading to uncover what makes this cave so special, from its fascinating history to what you can do while you’re there, and how to make sure you can get a spot on a tour.
About
Inner Space Cavern, located in Georgetown, Texas, is a stunning underground world that’s been hiding beneath the surface for thousands of years.
Discovered by accident in 1963 during highway construction, this limestone cave system stretches over almost 5 miles and is filled with dramatic rock formations, stalactites, stalagmites, and winding passages.
Today, visitors can explore part of the cave system and experience this natural wonder.
It’s one of the best-preserved caves in Texas, offering a chance to step into a different world and explore the natural beauty that’s been forming for millions of years.
History
The story of Inner Space Cavern begins millions of years ago, during the Cretaceous period, when much of Texas was covered by a shallow sea.
Over time, layers of limestone were deposited, which would eventually become the foundation for this hidden cave system.
Fast forward to the Ice Age, when underground water continued to carve out the intricate passageways and chambers you can see today.
💡 Natural entrances to the cavern closed approximately 14,000 years ago, leaving it hidden until its accidental discovery in 1963.
For thousands of years, the cave lay undiscovered, sealed off from the outside world.
However, evidence suggests animals like mammoths and saber-toothed cats may have accidentally fallen in, leaving behind fossilized remains that still fascinate researchers.
The Accidental Discovery
The modern discovery of the caverns came in 1963, and it was purely accidental.
Construction crews working on Interstate 35 drilled into what seemed like an empty void beneath their equipment as a drill bit suddenly dropped 26 feet!
Geologists were called in, and the hidden cave system was revealed in all its glory.
Once they realized the significance of what they’d found, a team of experts from the Texas Speleological Association began exploring and carefully mapping the cave.
The exploration meant over 7000 feet of passageways were documented.
By 1966, Inner Space Cavern was opened to the public, allowing people to marvel at its ancient formations and rich geological history.
Up to present day a total of around 4.76 miles of passages have been documented making it the 5th longest cave system in Texas!
Tourists can’t access all of these passages, but luckily there are guided tours that explore some of the areas.
There are still unexplored sections of the cave system so there could be even more interesting discoveries to come in the future.
To this day, it remains a preserved slice of Texas’ past, giving you the rare chance to see the forces of nature frozen in time.
What Makes It Unique?
One thing that’s particularly different about this cave system is the presence of ice-age animal remains like mammoths and saber-toothed cats.
This is something that you can’t find in any other caves in the area and altogether there has been over 40 different species of animals found in the cave.
Things To Do
The main draw here is the variety of guided tours, each offering a unique way to experience the cave’s natural wonders.
The guided tours include:
- The Adventure Tour
- The Hidden Passages Tour
- The Wild Cave Tour
Adventure Tour
If you’re looking for a family-friendly stroll, the Adventure Tour takes you along well-lit pathways with a guide sharing fun facts and pointing out the most impressive formations.
- Duration: 1 hour 15 minutes
- Difficulty: Beginner
- Age: All Ages
Hidden Passages Tour
If you want a bit more adventure then the Hidden Passages Tour ventures deeper into the cave’s darker, less-explored sections.
It gives you more of a taste of what early explorers experienced.
This one is a bit more rugged so it is not recommended for guests with physical limitations or claustrophobia.
- Duration: 1.5 hours
- Difficulty: Intermediate
- Ages: 7+
Wild Cave Tour
And if you’re up for an even bigger challenge, the Wild Cave Tour lets you truly channel your inner spelunker.
You’ll be able to crawl and climb through unlit areas with nothing but a helmet and headlamp.
This tour is physically demanding but does not require previous experience.
- Duration: 3.5 – 4 hours
- Difficulty: Advanced
- Ages: 13+
Beyond The Tours
Apart from the tours, the cavern offers some extra activities to make your visit even more memorable.
Check out the on-site fossil exhibits showcasing prehistoric bones unearthed in the cave, or swing by the gift shop for unique keepsakes.
Above ground, there’s also a mining area where kids (or the kid in you) can pan for gemstones and fossils.
You can also experience The Saber Tooth zip ride where you go backwards 130ft in the air, stop at the top briefly for some views, then come back down at 33mph!
Know Before You Go
Before heading to Inner Space Cavern, there are a few key details to keep in mind to make your visit as smooth as possible.
Opening times
The Inner Space Cavern is open every day of the year except Thanksgiving, Christmas Eve, Christmas Day, and Easter Day.
At the current time of writing the opening times are as follows as per the Inner Space Cavern website:
September 3, 2024 through May 23, 2025:
- Monday – Friday 9am-4pm
- Saturday – Sunday 10am-5pm
*The last tour enters the cave 15 minutes before closing.
May 24, 2025 through September 1, 2025:
- Open Daily 9 a.m. to 5 p.m. (summer hours)
It’s best to check the website for the most up to date times in case of any changes.
Tickets and Prices
Depending on which tour you want to take there are different ways to buy the tickets.
Adventure Tour
You must buy the ticket on arrival and they are sold on a first come, first served basis at the caves.
Prices:
- Adult: $23.95 – $24.95
- Child (Ages 4-12): $17.95 – $18.95
- Kids under 4 go free.
Hidden Passages Tour
These are sold on a first come, first served basis at the caves.
Prices:
- Adult: $28.95 – $29.95
- Child (Ages 4-12): $20.95 – $21.95
Wild Cave Tour
You must reserve this at least 2 weeks in advance by getting in touch with Inner Space Cavern (we’ve included contact details further below).
Prices:
- $125 per person.
Since 2 of the tours are first-come, first-served, arriving earlier in the day can help you avoid long waits during busy times like weekends or school holidays.
On a normal day expect to wait less than 30 minutes but longer during busier times like holidays.
Getting There
Inner Space Cavern is located right off Interstate 35 in Georgetown, Texas, about 30 minutes north of Austin.
You’ll find it next to IH-35 at exit 259 and there’s plenty of signs leading to the entrance once you get close.
There’s also free parking on-site which is nice.

Here’s the Address and the Google Maps listing:
- 4200 S I-35 Frontage Rd, Georgetown, TX 78626, United States
- Google Maps link: Inner Space Cavern
More Info / Contact Details
Make sure to check out their website where you’ll find the most up to date information about pricing and opening times.
You can also follow their Facebook page to stay up to date with any special events.
Contacting Inner Space Cavern
If you have any specific queries that aren’t answered on their website it’s best to email or call them using the details below:
- Email: [email protected]
- Contact number: +1 512-931-2283
Here’s a short video about the place for some extra information.
Things to Do Nearby
Once you’ve explored the depths of Inner Space Cavern, there’s plenty above ground in Georgetown and the surrounding area to keep the adventure going.
Georgetown Historic Downtown Square
Just a few minutes away, you’ll find Georgetown’s historic downtown square, known for its small-town charm, local boutiques, and excellent dining spots.
You can stop by places like Monument Café, a retro-style diner famous for its fresh comfort food and incredible pies.
There’s also the Williamson Museum which offers a peek into the area’s past with interactive exhibits and guided tours.
Farmers Markets
The Georgetown Farmers Market and the Wolf Ranch Farmers Market are also fun ways to sample local produce and handmade goods.
Lake Georgetown
If you love the outdoors then Lake Georgetown is a perfect place to spend a relaxing afternoon.
You can hike, swim, or even have a picnic by the water.
The lake’s trails offer great views and are family-friendly.
The Gault Site
This is one of the oldest archaeological sites in Texas with artifacts that changed the whole understanding of human history in the Americas.
Related Reading: Archaeologists Found THIS in Texas and It’s Older Than The Pyramids
Berry Springs Park and Preserve
Berry Springs Park and Preserve offers a tranquil escape with walking paths and picnic areas.
You even get the chance to spot a few resident donkeys grazing nearby.
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