Gypsum Cave was once thought to be one of the oldest aboriginal sites in North America. The cave is 300 feet long and 120 feet wide and is filled with dry, dusty deposits in all six rooms.

When excavated in 1930-31, the cave yielded the skull, backbone, nine to twelve-inch claws, reddish-brown hair and fibrous dung of the giant ground sloth, a vegetarian species common in the more moist environment known here about 7,500 to 9,500 years ago. Bones from extinct forms of the horse and camel were also found.

Pieces of painted dart shafts, torches, stone points, yucca fiber string and other artifacts were found mixed in with the sloth dung. W hen the dung was dated at 8,500 B.C. by the radiocarbon method, it was believed the man-made tools were the same age. Two radiocarbon dates on the artifacts themselves, however, indicate that the ground sloth and man were not contemporaneous inhabitants of the cave. Man probably made use of the cave beginning about 3,000 B.C., long after the ground sloths had abandoned it.