The exhibition was created in 1966 and is part of the underground museum opened to the public in the same year.
The exhibition illustrates all issues connected with the Miocene salt deposits in the area of Wieliczka and Bochnia.
Every issue is presented in a separate glass case and illustrated by appropriate salt rock specimens. The most significant issues refer to the deposit structure and its genesis. The glass case entitled The wieliczka vein rocks in order of sedimentation displays the main types of salt, dividing them into lump and bed parts of the deposit. The most characteristic for the lump part of the deposit are: green salt, zuber, marly mudstone, while typical for the bed part are various types of spiza salt: striped salt, fine-grained salt and salt including large crystals of halite. Deeper parts of the deposit include the most precious and purest kinds of salt: staple shaft salt, green salt and the oldest salts discovered recently. The two groups are also displayed in separate glass cases. The comparison of specimens within one type shows their great diversity.