underground lake in wieliczka salt mines

arc arch archaeology architecture buildings cable cave ceiling cellar chamber chandelier chapel church coal corridor crystal dark deep elevator engineering equipment europe famous feature geology gray green heritage history horizontal horse illuminated indoors industry krakow lake landmarks levels lighting majestic material mine mineral mining museum mystery nature object obsolete old place poland rock rough saint salt sculpture shaft staircase statue steps stone surrounding technology tourism tourist transportation travel tunnel tunneling underground wall water wieliczka winch wood