One of the longest, uninterrupted running mines – Wielicka Salt Mine in Southern Poland operated from the 13^th century all the way to 2007. As such, the scale of excavation is extremely large. Totalling more than 200km in length, and seven storeys descending some 327 metres below ground, the mine consists of corridors, galleries and chambers, as well as underground lakes.

Besides being a mining museum, complete with tools and equipment dating back to the middle ages, Wielicka Salt Mine is also famous for its exceptional works of art, carved completely out of salt. Exhibits include statues of mythical and famous people, which were crafted first by the miners, and subsequently by contemporary artists. There is also an entire cathedral carved out of salt, where even the crystals on the chandeliers are carved out of rock salt.

The tour of the mine begins with a 378-step climb down to the 64-metre level of the mine, and after a 3-kilometre long tour, visitors will be 135 metres underground. An elevator, which takes 30 seconds to reach the surface, is then used to transport visitors up.