Sotho people
Stone tools from the Middle Stone Age show that the crater was regularly visited by people from as far back as 100,000 years ago in order to hunt and collect salt. Water in the crater comes from surface springs, ground water and rain water and is rich in dissolved carbonates and sodium chlorides. Tswana and Sotho people harvested the salt by filtering and decoction between 1200 and 1800. Between 1912 and 1956 brine was pumped from the floor of the crater by the company "SA Alkali Ltd." in order to extract soda and salt.