Dome (O'odham: Hi:lo) is a ghost town located in Yuma County, in southwestern Arizona, United States. Originally Swiveler's Station, 20 miles east of Fort Yuma, on the Butterfield Overland Mail route, a post office was established here in 1858. It was first under the name of Gila City the nearby boomtown 1 1/2 mile west of Dome but the post office closed July 14, 1863, after most of the town was swept away in the Great Flood of 1862, and then abandoned for the La Paz gold rush along the Colorado River. After the railroad passed by the site and an attempt to do large scale mining of the placers began, a new post office was established as "Dome" in 1892 but soon closed when the attempt failed. Subsequently it opened and closed several times before finally closing in 1940.
Today the site lies along the railroad and a road that follows the old Overland stage route, south of the Wellton-Mohawk canal and Gila River. All that remains on the site is a large adobe building, one small adobe remnant and foundations. There is a cemetery nearby to the west.