Sasolburg, town, northern Free State province, South Africa, south of Johannesburg. Established in 1954, it was built by Sasol Ltd. (the former South African Coal, Oil, and Gas Corporation Ltd.) to house employees at the world’s first oil-from-coal plant producing commercial quantities of oil. The location was selected for its proximity to large coal deposits, the Vaal River, and the Witwatersrand markets. A variety of petrochemicals are also produced. Sasolburg attained official town status in 1967. Pop. (2001) 24,571.