[8] Although this region is a desert, with high temperatures and low average rainfall of 3 inches (76 mm) per year,[9] the economy is strongly based on agriculture.

This would lead towards the start of the Yuma War, with a Quechan-led coalition of tribes against the US army and their indigenous allies in Baja California and Sonora.

[14] In 1905, torrential rainfall in the American Southwest caused the Colorado River (the only drainage for the region) to flood, including canals that had been built to irrigate the Imperial Valley.

Rival Mexican armies affiliated with different ethnicities killed nearly 10,000 farmers and their families in northern Mexico.

Not until the 1920s was the other side of California in the United States sufficiently peaceful and prosperous for the company to earn a return for a large percentage of Mexicans.

During the Great Depression and the Dust Bowl, the county attracted migrating "Okies" from drought-ridden farms on the plains by the need of migrant labor.

It was to defend the newly settled community of Yuma, Arizona, on the other side of the Colorado River and the nearby Mexican border.

In March 1851 the post was moved to a small elevation on the Colorado's west bank, opposite the present city of Yuma, Arizona, on the site of the former Mission Puerto de Purísima Concepción.

[17] NAF El Centro is the winter home of the U.S. Navy Flight Demonstration Squadron, The Blue Angels.

NAF El Centro historically kicks off the Blue Angels' season with their first air show, traditionally held in March.

The expansive dune formations offer picturesque scenery, a chance to view rare plants and animals, and a playground for ATV and off-roading enthusiasts.

[21] The Colorado River streams through the southwestern United States and northwestern Mexico, approximately 1,450 miles (2,330 km) long, draining a part of the arid regions on the western slope of the Rocky Mountains.

Knight refused substantial donations of money and labor from supporters who wished to modify his message of universal love to favor or disfavor particular groups.

The park features many sweeping vistas, washes (wadis), rocky outcrops, boulder-strewn hillsides, in addition to the vast expanses of sandy desert; in springtime (especially after periods of rain), these areas appear to change shape, as they come alive with blooming wildflowers, flowering and fruiting cacti and numerous other species of native flora.

Fauna that visitors may also have the chance to see include the bobcat, coyote, golden eagle, kit fox, mule deer, mountain lion, red-tailed hawk and roadrunner, as well as the iconic desert subspecies of bighorn sheep (formerly more common, across the southwest U.S. and northern Mexico).

The fossils here are not necessarily of dinosaurs; more commonly found are ancient oyster and seashell, coral, and other marine life from the prehistoric Miocene epoch, when the entire area was submerged as part of the Western Interior Seaway.

[25] The Painted Gorge, located on the eastern side of the Coyote Mountains, consists of sedimentary, metamorphic and igneous rock; Heat and movement over time has created fantastic shapes and colors.

The river and its associated backwater lakes and wetlands are a green oasis, contrasting with the surrounding desert mountains.

Because of its southern latitude, elevation, and location in the Colorado Desert, the refuge experiences some of the highest temperatures in the nation.

Imperial County is roughly twice the size in total square miles as the State of Delaware.

The Chocolate Mountains are located east of the Salton Sea, and extend in a northwest–southeast direction [30] for approximately 60 miles (97 km).

The southernmost strands of the San Andreas Fault connect the northernmost extensions of the East Pacific Rise.

[55][56] Previously strongly Republican, Imperial County was a Democratic stronghold in presidential, congressional, and local elections until 2024.

[61] However, on February 6, 2012, the United States Court of Appeals for the Ninth Circuit denied Imperial County legal standing in the case Hollingsworth v.

[69] Although this region is a desert, with high temperatures and low average rainfall of 3 inches (76 mm) per year, the economy is heavily based on agriculture due to irrigation, which is supplied wholly from the Colorado River via the All-American Canal.

Imported water and a long growing season allow two crop cycles each year, and the Imperial Valley is a major source of winter fruits and vegetables, cotton, and grain for U.S. and international markets.

[75] This is driven in part by California's mandate to generate 20% of its power from renewable sources by the end of 2010, the valley's excellent sun resources, the high unemployment, its proximity to large population centers on the coast, and large tracts of otherwise unusable desert land.

As of April 2008, the BLM has received 163 applications to build renewable energy projects on 1,600,000 acres (6,500 km2) in California.

[75] Stirling Energy is currently building one of the world's largest solar thermal plants, 10 square miles (26 km2) with 38,000 "sun catchers," it will power up to 600,000 homes once it is fully operational by around 2015.

[79] † county seat 442/760 – Covers all of the El Centro metropolitan area as well as Palm Springs, Oceanside, Bishop, Ridgecrest, Barstow, and Needles; northern San Diego County; and southeastern California, including much of the Mojave Desert and the Owens Valley.