Merkers Have their own web site visit it here

"Join us on an exciting journey at a depth of about 500 meters. Be amazed by sights such as the hall-like great bunker with the largest underground bucket wheel excavator in the world or the crystal grotto which was discovered only in 1980 and contains salt minerals up to a meter in height! Or peek into the so-called gold room where the entire gold and currency reserves of the Third Reich were stored at the end of the war. Come and visit us, we look forward to seeing you!"