Today many people think of Yuma as a convenient stop between Phoenix or Tucson and San Diego—and this was equally true in the relatively recent past. It's difficult to imagine the lower Colorado River, now dammed and bridged, as either a barrier or a means of transportation, but until the early part of the 20th century this section of the great waterway was a force to contend with. Records show that since at least 1540 the Spanish were using Yuma (then the site of a Quechan Indian village) as a ford across a relatively shallow stretch of the Colorado.
Three centuries later, the advent of the shallow-draft steamboat made the settlement a point of entry for fortune seekers heading through the Gulf of California to mining sites in eastern Arizona. Fort Yuma was established in 1850 to guard against Indian attacks, and by 1873 the town was a county seat, a U.S. port of entry, and an army depot.
The steamboat shipping business, undermined by the completion of the Southern Pacific Railroad line in 1877, was finished off by the building of Laguna Dam in 1909. During World War II Yuma Proving Ground was used to train bomber pilots, and General Patton readied some of his desert war forces for battle at classified areas near the city. Many who served here during the war returned to Yuma to retire, and the city's economy now relies largely on tourism. The population swells during the winter months with retirees from cold climates who park their homes on wheels at one of the many RV communities. One fact may explain this: according to National Weather Service statistics, Yuma is the sunniest city in the United States.