Contemporary knowledge on the beginnings of the salt industry in the Polish lands is a result of thorough scientific research which has been conducted since the 1960s. Publications of archaeologists and historians (especially S. Fischer, A. Jodłowski, A. Keckowa, J. Piotrowicz and J. Wyrozumski) showed that the area of the oldest salt processing and the oldest mining of rock salt is Małopolska.
Traces of the first Saltworks producing salt from surface salt waters derive from the Middle Neolithic period (3,500 B.C.). They were discovered in Barycz near Wieliczka. In historical times, between the 11th and the 12th century, Wieliczka was the largest salt processing centre in Małopolska, listed for the first time as Magnum Sal (i.e. Great Salt) in a document of the papal legate Giles, dated by medievalists from the years 1124/ 1125 (the date 1105 included in the document was probably added in the 13th century).a
Discovery and launch of the exploitation of rock salt deposits took place in Bochnia in the middle of the 13th century. This fact was recorded in the “Cracow Capitular Yearbook” (Rocznik Kapitulny Krakowski) under the date 1252: “Sal durum in Bochnia est repertum, quod nunquam ante fuit” (“In Bochnia rock salt was discovered which had not been heard of before”). The oldest mining (exploratory) shaft also derives from this period; it was discovered in the courtyard of the Saltworks Castle in Wieliczka (currently, after reconstruction of the casing, it is accessible for visitors in the form of an archaeological and mining reserve). The beginnings of the exploitation of rock salt in Wieliczka on an industrial scale are connected with the construction of the Goryszowski shaft, dated by historians at the 1280s.
A direct result of the exploitation of rock salt was the conferring of municipal rights: to Bochnia in 1253 and to Wieliczka in 1290. The first written reference to rock salt in Wieliczka is included in the city’s incorporation charter of 1290, whereas quick progress in its production is confirmed by the fact that in 1291, Oświęcim received the right to store salt; Oświęcim was a city along the salt sale route from Wieliczka to Silesia.
At the end of the 13th century, an enterprise called “Cracow Saltworks” was developed, comprising salt mines in Wieliczka and Bochnia along with the Saltworks located there. It continued to operate in this organisational form for almost 500 years, until the first partition of Poland (1772), being the largest enterprise of this type in the Republic of Poland and at the same time one of the largest in Europe.
Salt was the most important mineral in the Polish state and, according to a binding law, it was the property of the ruler (the so-called salt regality). It is estimated that at the time of King Casimir the Great (14th century), revenue from the sale of salt constituted 1/3 of the state treasury income. The heyday of Cracow Saltworks was between the 16th and the middle of the 17th century. The mining staff had approx. 2,000 people, and production exceeded 30,000 tonnes. In the 17th century, salt was extracted in Wieliczka from three mine levels, and eight shafts were made (including the shaft that is currently used for servicing tourist traffic, the Daniłowicz shaft). The very first maps of the Wieliczka mine were made at this time. Long-term wars, the plagues that accompanied them and natural disasters shook the salt economy in the middle of the 17th century, and the lessors managing the Saltworks neglected protection works, contributing to the mine’s ruin. It was only in the following century when specialists from Saxony arrived, led by J. G. Borlach, that they managed to improve the enterprise’s operation with respect to the organisational and technical aspects.
The Austrian times (1772 – 1918) are characterised by a huge increase in production, leading to spatial extension of the Wieliczka mine, mechanisation of mining works (steam and electric machines), employment of professional engineering staff and setting out the first tourist route for visitors.
In 1913, modern Saltworks were commissioned in Wieliczka, offering a number of new employment positions and perspectives of production development, pursued consistently at the time of the Second Republic of Poland. New technology introduced at that time, consisting in the process of salt leaching under the ground, allowed for the obtaining of high production indexes and extending the mining operation of the enterprise. Extensive exploitation and neglect of ongoing protection works exerted a negative impact on the stability of the rock mass and the mine’s condition. After WWII, an idea emerged to flood it. In 1964, extraction of rock salt came to a halt in Wieliczka, whereas on June 30, 1996, exploitation of the deposit was ceased entirely. Currently, the picturesque mining pits are used for touristic, museum and medicinal purposes.
The Wieliczka salt deposit comprises an area of 5.5 km (along an East-West line) with a width ranging from 0.5 to 1.5 km (North-South). Over the course of seven centuries, 26 open-top shafts and 180 fore-shafts connecting individual levels were drilled. Mining exploitation of the deposit was commenced on level I (57 m under ground level), finally reaching level IX (327 m in depth). 2,350 chambers were drilled and over 240 km of drifts. In spite of the existing hazards (water, cave-in, gas), the pits in the Wieliczka mine are characterised by greater durability that ore mines; thanks to this, chambers dug out at the end of the Middle Ages and at the beginning of the modern age have been preserved to this day. A historical zone was separated in order to ensure better protection for the 700 year-old mine. According to the status of 2004, the historical zone comprises 218 chambers and 190 drifts on levels from I to V, including 20 chambers and drifts rendered available for visiting along the Tourist Rote (from levels I to III) and 16 in the Cracow Saltworks Museum (level 3). The basic objective of the mining work currently conducted underground is protection of the historical substance. The chambers of the Tourist Route, the Museum and other precious chambers in the mine are being protected against cave-ins by modern bracing methods, or, as in the past, supported by wooden cribs (support columns). The salt mine in Wieliczka has the status of a monument and is included under legal protection. In 1976, it was entered into the register of national monuments, and two years later it was entered into UNESCO First World Heritage List. By means of the order of the President of Poland of September 8, 1994, it was proclaimed a Historical Monument.