Photographer: Kevin Stillman

Fantastic caverns are called unbelievable by cave authorities. Formations called "impossible" grow in delicate crystal beauty and amazing profusion on ceilings, walls, and floors. A past president of the National Speleological Society said, "This is the most indescribably beautiful cavern in the world. Its beauty cannot be exaggerated, even by Texans!" Guided cave tours regularly each half hour cover about 1.5 miles under ground. (Rest stops provided, but tours are strenuous-equivalent to climbing several hundred steps.) West of Sonora about 8 miles, exit I-10 on Caverns of Sonora Road (R.M. 1989); drive south about 7 miles. Camping area with hookups available. Admission fee. For more information, call 325/387-3105 or 325/387-6507.