The Turda Salt Mine is located in the Durgău-Valea Sărată area of Turda . The entrance to the salt mine (through the Franz Josef access gallery) was until 2010 from 54A Salinelor Street ( Turda Nouă district ), currently through the new and modern entrance from the Salina-Durgău tourist center (Durgău Alley no. 7).
Turda Salt Mine is included on the list of historical monuments in Cluj County , drawn up by the Romanian Ministry of Culture in 2015 ( LMI code CJ-II-mA-07801 ).
Geological data[ edit | edit source ]
The salt deposits in Transylvania (systematically exploited over time at Ocna Dejuliu , Cojocna , Turda , Ocna Mureș , Ocna Sibiului and Praid ) were formed 13.5 million years ago, in a shallow sea and under a tropical, very warm climate. The salt layer extends everywhere in the subsoil of Transylvania, having a thickness of about 400 m. The thick layers of sediments subsequently deposited on top of the salt layer pressed with immense weight the malleable (plastic) layer of salt, which sought weaker areas of the earth's crust at the edge of Transylvania, where it rose in the form of mushrooms with heights of over 1,000 m, often reaching even the surface of the earth (the case of the localities with old salt exploitations mentioned above). In Turda, the salt mushroom has a height of about 1,200 m (researched through relatively recent drilling).
History of salt mining[ edit | edit source ]
Reliable archaeological evidence of salt exploitation at Durgău-Turda exists from the pre-Roman period (50 BC-106 AD) [ 1 ] . The Romans (106-274 AD) exploited salt at Durgău in pyramidal chambers 17-34 m deep and 10-12 m wide. In addition to the salt massif at Durgău, the Romans also exploited the neighboring salt massif at Băile Romane (in the area of the current swimming pool). Volker Wollmann in his monograph on mining [ 2 ] emphasizes the presence in the immediate vicinity of the salt deposits, each time, of a Roman fortification. The Roman castrum Potaissa defended the salt exploitations at Turda. The Romans worked only on the surface, in quadrangular pits, up to a depth of 12-15 m, from where the salt could be easily removed on slippery bridges and with simple lifting devices, after which they would leave it and start another. This is how the Romans extracted salt all over Transylvania, and the abandoned excavations became lakes.
After the Roman withdrawal in 274, until the 11th century, there is no clear evidence that salt extraction continued.
The first known document to date referring to the salt from Turda, issued by the Hungarian chancellery in 1075 , mentions the customs of the salt mines from Turda (Torda) in a place near the Aries River "qui dicitur hungarice Aranas (Aranyos), latine autem Aureus" ( "in the place called in Hungarian Aranyos, and in Latin Aureus" ) [ 3 ] . This customs point was located near the former Roman bridge (used throughout the Middle Ages, until the end of the 18th century), on the site of the fortified settlement later called Szentmiklos (St. Nicholas).
During the 13th century, the existence of the Durgău-Turda salt mine is explicitly mentioned. Thus, on May 1, 1271 , the "salt mine of Durgău-Turda (Dörgö-Torda)" was given to the chapter of the Bishopric of Transylvania . [ 4 ]
Austro-Hungarian period[ edit | edit source ]
During the Hungarian rule of the Turda Salt Mine from the 15th to 18th centuries, a number of 4 underground ogival mines were opened in Durgău: Katalin Mine , Horizont Mine ( Nagydörgö = Great Durgău ), Felsö-Akna Mine ( Obere Grube = Upper Ocna , Grosse Grube = Great Ocna , Karoline = Carolina ) and Joseph Mine ( Iosif ).
The establishment of Habsburg (Austrian) power in Transylvania at the end of the 17th century and the increase in the material needs of society, determined that, starting from the second half of the 17th century, the importance given to the branches of the extractive industry (including salt exploitation) increased significantly. The Durgău-Turda salt mine implicitly came under direct Austrian administration. [ 5 ]
During the Austrian rule of the Turda Salt Mine from the 17th to 19th centuries, 5 underground mines were opened in Durgău: Mina Terezia (initially after St. Teresa of Ávila , later after Empress Maria Theresa ), Mina Anton (after St. Anthony of Padua ), Mina Cojocneană (Kolozser), Mina Rudolf [ 6 ] and Mina Ghizela .
In 1690, the opening works of the bell-shaped Terezia Mine began. Two other bell-shaped salt mines followed ( Anton and Cojocneană ), then two mines with a modern trapezoidal profile ( Rudolf and Ghizela ). In 1857, the tunnelling gallery of the new Ghizela mine unexpectedly intercepted an unknown old mining work. The purpose and dating of this old work (probably a shaft) is uncertain (Roman period or early Middle Ages).
Interesting information regarding the exploitation of the Turda salt mines is documented in 1767, through the publication in Cluj of the work of the Jesuit mineralogist Joanne Fridvaldszky. [ 7 ] He thus describes the situation of the mines and salt cutters in Turda in that year: The Turda Salt Mine has five major mines, the first of which is called Superior [ 8 ] , the second Inferior [ 9 ] , the third Colosiensis [ 10 ] , the fourth S. Theresiae , and the fifth S. Antonii . The diameter of the base of the Superior mine was 85 m (45 fathoms and two feet), and the height was 104 m (55 fathoms and two feet). The salt from this mine was clean and only rarely contained a slight mixture of earth, it was dug by 87 cutters (fossores), helped by 18 volunteers (volontes). The diameter of the Inferior mine was 68 m (36 fathoms and six feet), and the height was 100 m (53 fathoms). In terms of the quality of the salt, the Inferior mine was no different from the Superior mine, the work being carried out by 75 cutters and 18 volunteers. The Colosiensis mine had a diameter of 76 m (40 fathoms) and a height of 111 m (59 fathoms). 63 cutters worked in this mine together with 12 volunteers. The S. Theresiae mine had 30 cutters and 15 volunteers, had a basal diameter of 50 m (26 fathoms) and a height of 66 m (35 fathoms). The newest S. Antonii mine had dimensions commensurate with the others. The mineralogist Fridvaldszky recalled the existence of a larger and older mine which, due to the danger of collapsing, was closed on June 19, 1762 (today: Lake No. 2 Durgău).
The Josephine map from 1769-1773 shows that there were 5 salt mines in Turda at that time (Carolina, Iosif, Terezia, Anton and Cojocneană).
In 1780 , there were 5 ogival salt mines in Turda:
- "Die Obere Grube" ("Ocna de Sus", "Felsö-Akna", "Ocna Mare"): 125 m depth, 228 m basal perimeter.
- "St. Josephi" ("Iosif"): 49 m depth, 66 m basal perimeter.
- "Maria Theresia" ("Terezia"): 76 m depth, 167 m basal perimeter.
- "St. Antoni" ("Anton"): 63 m depth, 129 m basal perimeter.
- "Koloscher Grube" ("Ocna Cojocneană"): 122 m depth, 234 m basal perimeter. [ 11 ]
"Die Obere Grube" led, after the collapse of a wall and ceiling, to the formation of lake no. 1 (Lake Carolina), clogged in the 1980s-1990s following massive landslides near Agriculturii Street [ 12 ] . On Johann Fichtel's map from 1780 [ 11 ] , two other old pits, already abandoned and collapsed, are marked, which correspond to lake no. 3 (Lacul Dulce) and lake no. 4 (Lacul Ocnei). On the site of lake no. 2 (Lacul Durgău) Johann Fichtel indicates a dry, round-shaped surface with salt outcrops, where there was another old salt exploitation. Lake no. 5 (Lacul Rotund) would also have been created by the collapse of an old pit.
František Pošepný reported in detail about the active and inactive salt mines at the Turda Salt Mine in 1867. [ 13 ]
Between 1853 and 1870, the first 780 m of the Franz Josef access gallery were dug (to facilitate the transport of salt to the surface), then, by the end of the 19th century, another 317 m were dug, reaching the final length of 917 m, of which 526 m in the surrounding barren rocks and 391 m in the salt massif. 850 m can be visited (67 m are inaccessible). On the left wall (from the direction of the old entrance to the salt pan, Salinelor Street) of the Franz Josef coastal gallery, before the gallery enters the salt, there is the following acrostic (encrusted during the excavation of the gallery): KFJ Fü. Sb. ( König F ranz J osef F urest von S ieben b ürgen = King Franz Josef, Prince of Transylvania ).
In 1896, 3 salt mines were opened in Turda [ 14 ] .
Modern period[ edit | edit source ]
The exploitation of salt in the Turda Salt Mine was definitively stopped in 1932, due to primitive technical equipment, low efficiency and competition from other Transylvanian salt mines.
In 1932, the following salt mines existed at Turda Salt Mine (from south to north):
- Iosif mine (1740-1900)
- Rudolf mine (1864-1932)
- Terezia mine (1690-1880)
- Ghizela mine (1857-1932)
- Anton mine (early 18th century-1862).
Turda Salt Mine reopened in 1992 (for tourist and curative purposes) and is open all year round. In 2017, the former Iosif , Rudolf , Ghizela and Terezia mines were open to the public . Also worth seeing are the well-preserved medieval equipment from the mine (unique in Europe), such as the blacksmith shop, the salt press and the salt mill. Also, the Altar (carved into the salt wall) and the Staircase of the Rich (a staircase intricately crafted in wood).
With the financial support of the European Union, extensive works were carried out in 2009 to develop the Turda Salt Mine for tourist and curative purposes. The inauguration took place in January 2010 , after 2 years of work and 6 million euros invested. [ 15 ] The Turda Salt Mine currently has treatment rooms, an amphitheater, sports halls, and a "ferris wheel", from where you can admire the salt stalactites. [ 15 ]
Between 2012 and 2014, a 50 m long connecting tunnel was built between the Terezia mine and the Iosif mine, in order to include the Iosif mine, previously not open to public access, in the tourist circuit.
Salt transportation[ edit | edit source ]
The salt was taken to the pier at Mirăslău by ox-drawn carts, where it was loaded onto rafts, from where it was taken down the Mureș to the port of Alba Iulia. Salt could never be transported on rafts on the Arieș due to the waterfalls on the Mureș from Gura Arieșului, immediately after the Arieș flows into the Mureș. Water transport would also have been hindered by the numerous waterfalls-thresholds along the Arieș course, up to the flow into the Mureș, produced by hard layers of volcanic tuff. The largest waterfall at Gura Arieșului is about 3-4 m high, over which the rafts could not have passed, without capsizing.
The technique of opening salt mines in the past[ edit | edit source ]
Before opening a new salt mine in Transylvania, exploration drillings were usually carried out. [ 11 ] If salt was not intercepted up to a depth of 36 m (18 Klafter = 18 stänjen), the project was abandoned, due to the excessive depth of the wells. Ideally, the soil should have a thickness of max. 10-12 m (5-6 stänjen). If the first drilling was positive, a second one was carried out, at a distance of 6 m (3 stänjen) from the first, in order to establish the exact thickness of the covering layer above the second well. The second well was preferably located at the same elevation as the first or with a max. 4-6 m (2-3 stänjen) difference in level with the first well. One shaft was reserved for the entry and exit of miners from the pits (with the help of hemp ropes), and the other shaft for extracting salt from underground. The shafts were dug with a square profile, each side having 2.8 m (9 steps; 1 step = 0.3 m) to a depth of 4 m (2 stanzas) below the sterile-salt contact, after which they gradually widened over the next 4 m (2 stanzas), with a square profile as well. Here the so-called “foundation” was made, made of wooden beams embedded in the salt, on which the entire shaft rested. Then the shaft was reinforced, from the bottom up, at first with a mixture of clay, chaff and sheep wool (for waterproofing the walls), then with wooden beams (beams). The thickness of the reinforcements was 0.3 m (1 step), so that the effective profile of the shaft was finally reduced from 2.8 x 2.8 m to 2.5 x 2.5 m. From the barren-salt level down, the walls were lined with buffalo hide, which prevented direct contact of the water with the salt walls. The water that dripped into the mine was nevertheless captured and brought to the surface. From the “foundation” level down, the excavation was carried out with an increasingly wide, conical profile, so that after another 8 m (4 fathoms) the 2 adjacent shafts joined. From here, the mine took on a conical-ogival shape with a section as circular as possible (which was practically only rarely achieved). The mine was declared ready for exploitation only after an agent of the saltworks administration, standing on a lump of salt in the middle of the shaft, could no longer touch the ceiling of the shaft with his hammer. From this moment on, the salt cutters' salary was reduced from 4.5 Kreuzer (4.5 Kreuzer) per block of salt to the usual rate of 1.5 Kreuzer. The mine was then officially put into operation, and also received a name. The opening costs of a salt mine usually amounted to over 5,000 silver florins (gulden).