Salt Mine in Wieliczka
The Mine, which is in fact an underground town is counted among the unofficial wonders of the world. Salt was produced in Wieliczka as early as 3500 BC. Over the years 2040 chambers were cut into solid salt rock on nine levels of which 224 are considered historic with depths ranging from 57 to 330 meters. A system of drifts and shafts totaling 350 kilometers in length links the chambers.
Over the centuries miners carved magnificent chapels and charming underground lakes as well as dozens excavation activities can be found in the mine. The route accessible to visitors is a 3.5 kilometer long section situated 64 to 135 meters below the surface. The 12 meters high St. Kinga`s Chapel with magnificent salt chandeliers never fails to impress visitors. The chapel which is 55 meters long and 17 meters wide can accommodate as many as 500 people.
Another attraction of the mine is the spa situated 135 meters below the surface in the Wessel Lake chamber. Respiratory diseases nose, sinus, throat and larynx infections asthma, chronic obstructive lung disease as well as allergies, skin diseases and metabolic disorders are treated in the healthy microclimate of the salt chambers.
If you are interested and you can go there, you can find more here