Inner Space Cavern
Inner Space cavern was discovered by a Texas Highway Department core drilling team in the Spring of 1963. Six inch core samples were taken to determine if the ground was stable enough to support a large highway overpass. As they were drilling one of the test holes, the bit suddenly dropped 26ft. and the highway crew knew there was something down there besides rock.
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Bluespring Caverns
Over 50 smaller streams contained in 18+ miles of known passages combine in the main river passage to create America's longest navigable underground river. Living in the miles of flowing streams are rare blind cavefish and blind crayfish. Passengers on the custom electric tour boats can usually sight some of these unusual creatures as they float though the winding passages.
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