This 85-mile long canal brings water from the Colorado River to the citizens and agricultural industry of the Imperial Valley. The canal was completed in 1940, to replace a previous canal which served the same function, but traveled partly through Mexico (hence the name of the All American). The canal, one of the largest in the United States, travels through one of the hottest and driest places in the country, and is the sole source of water for the nation's fourth most productive, as well as most arid, agricultural region.