Salt's ability to preserve food was a foundation of civilization. It eliminated dependence on the seasonal availability of food and it allowed travel over long distances. Through the discovery of its use in food preservation it allowed for longer voyages, and it freed humans from dependence on fresh food. The merchants in the 12th century Timbuktu - the gateway to the Sahara Desert and the seat of scholars - valued salt enough to buy it for its weight in gold. This trade led to the legends of the incredibly wealthy city of Timbuktu, and fueled inflation in Europe, which was importing the salt. Until the 1900s, salt was one of the main movers of national economies and wars. Venice fought and won a war with Genoa over salt. Then, Genoa citizens Christopher Columbus and Giovanni Caboto destroyed the Mediterranean trade by introducing the New World to the market. The salt mines of Poland led to a vast kingdom in the 1500s, only to be destroyed when Germans brought in sea salt.

The Wieliczka Salt Mine near Krakow has been in continuous operation since the 13th century, leading it to be declared a UNESCO World Heritage site. The mine reaches down to a depth of 327 meters, and the labyrinth of its corridors is over 300 km long. It contains beautifully carved chambers, chapels, an underground lake, exhibits on the history of salt mining and statues of historic and mythic figures, all sculpted by miners out of the rock salt. Even the crystals in the chandeliers are fashioned of salt. The mine is justly referred to as "the underground salt cathedral of Poland." 

The mine is the second oldest operating salt mine in the world (the oldest one is in Bochnia, about 12 kilometers away) and as far back as the 18th century it was described by a visitor as being "as remarkable as the Pyramids and more useful". Salt deposits were discovered here in the eleventh century, and starting from the times of King Kazimierz the Great, the mining has been controlled by the crown. Currently there are nine levels, going to the depth of 327 meters and the tourist route covers only a small fraction of the entire mine (7.5 million square meters of post-excavation space). The most popular attractions are the enormous excavation chambers, the tallest being 36 meters high, and two others reaching 30 meters each. The tour includes a visit to three chapels, the oldest more than 500 years old and the newest one a mere 100 years old. The chapels are richly decorated with salt and wooden sculptures. The oldest salt sculptures date from the end of the 18th century. 

The largest of the chapels - Saint Kinga's Chapel located 101 meters below the surface is over 50 meters long, 15 meters wide, 12 meters high, and has the volume of 10,000 square meters. It is entirely carved out of salt, richly furnished with sculptures, bas-reliefs, and large chandeliers made with salt crystals. Another attraction along the tourist route are three underground salt water lakes, the deepest reaching seven meters in depth. Recently added "light and sound" performance is proving to be quite popular, as well. Signs of ancient mine works, wooden structures, machines and equipment hundreds of years old, are displayed along the tour route. All this is located within the underground scenery, remarkably rich in geological specimens which illustrate the complicated structure of this deposit. The illuminated underground beauty is most tangible.

An additional attraction of the mine is the underground microclimate which is supposedly beneficial for asthma sufferers. Quite often, doctors send their asthma patients here for an extended stay. The Wieliczka salt mine is an operating production complex which offers many varieties of salt for sale. There is measured iodized salt, dietetic salt for people with high blood pressure, salt tablets, bath salt, foot salt, and feed supplements for animals.