The Underground Mining Museum is one of the most unusual museums in Bulgaria. It is part of the 100 National Tourist Sites and is unique on the Balkan Peninsula. It is located in two of the preserved galleries of the first underground mine in this country – "The Old Mines" (1891). Their total length is about 630 meters.

50 meters underground, visitors to the museum can learn about the century-old history of coal mining - from manual mining and the removal of coal with wooden carts, through horse carriage, to electric locomotives and mechanized coal mining complexes.