Coal-mining began in Pernik in 1891 which soon became known in Bulgaria as the ‘town of black gold’. Extraction ceased in 1966, but from the 1980s public pressure grew for the creation of a museum, particularly after some former miners were inspired by a visit to the conserved salt mines at Wieliczka in Poland. Visitors are able to visit former galleries of a relatively shallow mine, some 50 km. beneath the surface. Protected by traditional miners’ helmets, they are able to progress along a former working some 630 m. long which houses displays that include the tools used by miners, telephones and other equipment used for communicating underground, safety devices and a locomotive supplied by Siemens to work in the mine in 1925. The museum headquarters is in a former mine office near to the underground galleries.