Inner Space Cavern

Name: Inner Space Cavern
Address: 4200 S. I-35 FRONTAGE RD., GEORGETOWN, TX, 78626, US
Telephone: 512-931-2283

A prehistoric cave discovered by accident, preserving Ice Age fossils and stunning formations.

Inner Space Cavern

The Experience

Prehistoric, humid wonderland

A Subterranean Discovery

Inner Space Cavern is a geological marvel, accidentally unearthed in 1963 by a Texas Highway Department drilling team working on I-35. After breaking eight drill bits, they punched through the limestone to reveal a vast network of over five miles of passages, making it Texas's fourth-largest known cavern. This ancient karst cave, formed in Edwards limestone, is a time capsule, preserving Ice Age fossils of creatures like mammoths, giant sloths, and saber-toothed tigers that met their end here tens of thousands of years ago.

Underground Wonders

Visitors can embark on various tours to explore this subterranean world. The basic guided walk showcases stunning formations such as stalactites, stalagmites, and flowstones. For a more adventurous experience, the Adventure Tour involves a half-mile hike through dripping water and pools, while the Wild Cave Tour offers an exhilarating journey over 1.2 miles through challenging passages. Along the way, marvel at prehistoric bone displays, artist murals depicting extinct creatures, and the unique borehole in the Inner Cathedral Room. Keep an eye out for rare, pigment-less cave-dwelling critters, known as troglobites, a testament to the cave's isolated ecosystem.

Know Before You Go

Wear closed-toe shoes with good traction, as cave floors can be wet and uneven. The cave maintains a constant 72°F with high humidity, so dress accordingly. While the cave itself doesn't flood, it's wise to check for any weather advisories before your visit.