As a tourist, I've been to a variety of different cave systems around the world. This one does not have the biggest caverns, but was impressive for the variety of the many interesting rock formations within the cave. Cost is reasonable and I didn't think the tour group was overly large (around 20 people), but I imagine during 'high' season it can get quite packed. A nice little trip if you want to get out of San Antonio (if you have a car) or are continuing your travel north of the city.
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