Inner Space Cavern is a developed show cave known for its 1963 highway-drilling discovery, decorated rooms, Ice Age bones, and varied tours.
MetricCave review status
Last reviewedMar 19, 2026
Reviewed byMetricCave Editorial
Review date reflects the latest MetricCave check of the planning details on this page.
Georgetown, Texas
Inner Space Cavern is built around an accidental I-35 discovery, big decorated rooms, Ice Age bones, and tours ranging from paved walks to real crawl-and-climb caving.
If you need hotels, gas, or groceries before the cave, Georgetown is the closest named town for Inner Space Cavern.
The History & Geology
The drill bit dropped 26 feet after passing through about 40 feet of limestone, and the first Texas Speleological Society team entered in November 1963 before surveying more than 7,000 feet of passage.
The cave opened to the public in summer 1966.
The standard route is a paved, lit, one-mile walk through the largest decorated rooms and lasts about 1 hour to 1 hour and 15 minutes.
Make a day of it
Inner Space Cavern is usually part of a broader visit around Georgetown.
