Fodor's Expert Review Colossal Cave Mountain Park

This limestone grotto 20 miles southeast of Tucson is the largest dry cavern in the world. Guides discuss the fascinating crystal formations and relate the many romantic tales surrounding the cave, including the legend that an enormous sum of money stolen in a stagecoach robbery is hidden here.

Forty-five-minute cave tours begin every hour on the hour and require a ½-mile walk and a climb of 363 steps. The park includes a ranch area with trail rides through saguaro forests (from $38), hiking trails, a gemstone-sluicing area, a petting zoo, a gift shop, and a café.