The shaft "Mikołaj" in Ruda Śląska was opened in 1912, and then it belonged to the mine "Wolfgang". In the postwar years, the shaft was part of the mine "Walenty-Wawel", which ceased to operate in the 90s the last century. Nowadays, the entire complex of the shaft structures belongs to the city. It is worthwhile to see an operating headframe e with a flywheel with a diameter of 6 m and a weight of 20 tons.