There were seven Limburg mines. Zolder was the last to close its doors. Operations only began in 1930, a latecomer. The preparatory work took no less than 23 years due to a series of setbacks.
You can visit the extraction machine building from 1924 and 1925, which houses a historic collection of compressed air compressors. One of the two headframes has been preserved, but the first, smaller air and material headframe was demolished after the closure of the mine.