This earthquake-formed cave is unique in that it is not harmed by touch or light, so visitors are free to take photos and touch the cave. Get an aerial view of the Balcones fault line from the Tejas Observation Tower. There also is a wildlife petting area, train ride, anti-gravity house and gift shop.
Open daily. Closed Christmas Eve and Christmas Day. See website for hours.
Exit 202 off I-35 to Wonder World Drive.