High Quality Content by WIKIPEDIA articles! Yuma Crossing is a site in Arizona and California that is significant for its association with transportation and communication across the Colorado River. It connected New Spain and Las Californias in the Spanish Colonial period in and also during the Western expansion of the United States. Features of the Arizona side include the Yuma Quartermaster Depot and Yuma Territorial Prison. Features on the California Side include Fort Yuma which protected the area from 1850 to 1885