The New International Encyclopædia/Colorado Desert

COLORADO DESERT. An arid region of southern California (Map: California, F 5). It extends from the eastern base of the coast ranges of San Diego County eastward to the Colorado River, and embraces the Coahuila Valley, which extends toward the northwest between the San Bernardino and San Jacinto Mountains. A considerable portion of the desert, including part of the Coahuila Valley, is below sea-level. At some prehistoric period part of this region was included in the Gulf of California, from which it was separated by the growth of the delta of the Colorado River. Later it formed the basin of a fresh-water lake, and in recent times a considerable portion of the area has been flooded from the river, so as to produce a temporary shallow lake, known as Salton Sea. The Southern Pacific Railroad crosses the northern part of this desert and traverses the Coahuila Valley. The Colorado Desert is but a portion of the great desert region of the southwestern United States, which includes also the Yuma and Mohave deserts.