El Camino Del Diablo, historic road in Pima and Yuma counties in Arizona, United States

El Camino del Diablo is a historic 250-mile (400 km) dirt road across the Sonoran Desert in Pima and Yuma counties, Arizona, running from Caborca, Sonora, through Sonoyta, Quitobaquito Springs, the Sierra Pinacate lava fields, the Tule Desert and Tinajas Altas to Yuma Crossing on the Colorado River. Its most difficult stretch, Sonoyta to Yuma, is 130 miles (210 km) long.

The trail served as a trade route between Spanish California and Arizona from the 17th century and was used by soldiers, settlers, and gold seekers during the 18th and 19th centuries. The name reflects the dangers travelers faced from extreme heat, scarce water, and harsh desert conditions.

The trail is accessible only with experienced navigation and thorough preparation, as there is minimal infrastructure and limited water sources. Visitors should expect extreme temperatures, require full equipment, carry adequate water, and need detailed terrain knowledge depending on the season.

At Tinajas Altas, nine rainwater pools sit one above another on a steep granite slope and can hold up to 20,000 US gallons when full. During the 1891–1896 boundary survey, a party told of three prospectors found dead just above the empty first tank, their fingers worn raw climbing toward the second, which held water.