The Pilsen underground was created gradually, starting at the time the town was founded. The cellars and corridors served not only as storage areas, but in times of danger also provided hiding places and escape routes from the besieged town. Today the system of interconnected corridors spreads out on two to three levels under the entire historical centre of Pilsen, it is at least 17 km long and archaeological findings are presented in it. A functional replica of a water wheel and a letterpress exhibition are a part of the 800-metre tour circuit.