A group of small stone enclosures, supposed by some to be of natural origin and by others to be the works of man, lies on a rocky travertine-encrtfsted talus slope at the base of the Santa Rosa Mountains on the west side of the Coachella Valley in Riverside County, California. These phenomena are known locally as the "Ancient Fish Traps." They occupy a series of rocky terraces some 90 feet below the maximum high-water shore line of Ancient Lake Cahuilla (called by some Blake Sea), whose basin is now partly occupied by the Salton Sea. The “traps” consist of 85 to 100 bowl-like depressions composed of a travertine-encrusted granite talus debris. They are arranged in three rows, each of which follows the exact contour of one of the old recessional terraces of the lake (Pl. XIX).
