Pittsburg is a city in Contra Costa County, California, United States. It is an industrial suburb located on the southern shore of the Suisun Bay in the East Bay region of the San Francisco Bay Area, and is part of the Sacramento–San Joaquin River Delta area. The population was 63,264 at the 2010 United States Census.
In 1849, Colonel Jonathan D. Stevenson (from New York) bought the Rancho Los Medanos land grant, and laid out a town he called New York of the Pacific. By 1850, this venture failed. With the discovery of coal in the nearby town of Nortonville, the place became a port for coaling, and adopted the name Black Diamond, after the mining firm that built the Black Diamond Coal Mining Railroad from there to Nortonville. Because of the industrial potential of the site, a name change to Pittsburg was proposed in 1909.
Pittsburg, originally settled in 1839, was called first "New York Landing", then "Black Diamond", before citizens voted on "Pittsburg" on February 11, 1911. The name was selected to honor Pittsburgh, Pennsylvania, as the two cities' shared a common steel and mining industrial heritage. This rechristening came at a time when the name of Pittsburgh, Pennsylvania was more commonly spelled without the "h".
In 1910, Columbia Steel opened its California steel plant in Pittsburg with one foundry and a crew of 60 employees. It made steel castings for the dredging, lumber and shipping industries.