El Dorado Commercial Historic District

On January 10, 1921, Dr. Samuel T. Busey finished a well a mile southwest of town. It produced for only forty-five days, but it set off a rush that turned a farm and lumber town of about 4,000 into the state's oil capital. By 1923 El Dorado had fifty-nine oil contracting companies, and with no beds to be had, tents and shacks filled whole neighborhoods. The population reached nearly 30,000 in 1925 and then fell to 16,241 by 1930. It has since been branded Arkansas's Original Boomtown.

The historic district is the commercial heart that boom built around the Union County Courthouse. Most of it is one- and two-story brick, with the nine-story Exchange Bank building, the county's first skyscraper, and the eight-story Murphy Oil building as exceptions. More than forty buildings count as contributing, and the National Register listed the district on August 21, 2003. The Murphy Arts District, which opened its first phase in 2017, now uses several downtown venues.

The town's record includes harder chapters. A young man named Albert Williams was lynched in El Dorado in 1883. On February 26, 1910, a gunfight reportedly broke out between a Black man and three white men outside a Black-owned barbershop, and an armed mob then shot at and vandalized storefronts in the primarily Black business district. The National Guard was called out, and a large share of the Black population left, many for Camden. Accounts of how it began differ, and it is unknown whether others were hurt or killed. Park once and walk the blocks around the courthouse.