Geological foundation of the Krakow
THE GEOLOGICAL FOUNDATION OF THE KRAKÓW TOWN, AN ANCIENT CAPITAL OF POLAND
by Jan Urban (dr)
Kraków (Cracow) is one of the most impressive towns of Poland, famous all over the world. It is abounding with historical monuments: several tens of churches built in Romanesque, Gothic and Baroque styles (Figs 1-3), Medieval arrangement of the city, the largest Central Square in Europe with the Renaissance “supermarket”, buildings of one of the oldest university in Europe founded in 1364 (Jagiellonian University), fragments of the Medieval ramparts etc. (Figs 4-7). Kraków was a capital of Poland from the 11th through 16th century, so the Renaissance King Castle built on the Wawel Hill (Figs 8, 9) towers over the Old City. The Wawel Hill has been populated since the Old Stone Age. Now the town is a great cultural and educational centre of European importance.
Historians try to explain the phenomenon of the foundation of Kraków agglomeration just in this place in some ways, but the reasons of its foundation is clear and simple for naturalists, especially for geologist. The reason of human settlement in this place was the geological structure of the area and the consequences of this structure in the geomorphic evolution of the Kraków area. In the geological sense, the Kraków town is situated in the narrowest part of the Carpathian Foredeep, formed in the Neogene as a tectonic depression on the northern foreland of the Carpathians which were just folded and moved to the north. The Neogene marine basin in this depression was gradually filled with soft claystones and siltstones, formed of material derived from the mounted Carpathians. Subsequently, after the sea withdrawal, in the Quaternary the depression was covered by sands and muds of Vistula river. Vistula river, the Queen of Polish Rivers, has used the depression as the most favourable way to carry water from the Carpathians to the Baltic sea.
But just in the narrowest segment of the Carpathians Foredeep, in Kraków, the sediments filling the depression are cut by the network of the tectonic faults and several uplifted tectonic blocks, formed of hard, Jurassic limestones of their substratum pass through the Neogene-Quaternary sediments. And these tectonic horsts form apparent hills towering over the flat and swampy areas of the Neogene-Quaternary depression and its rocks. The Wawel Hill is one of the highest and the most characteristic among them (Fig. 10).
Before the foundation of the town, the Wawel Hill was surrounded by meandering large and “lazy” Vistula river (Fig. 9), its tributaries, as well as lakes (old fragments of river bed) and swamps. So it was extremely convenient place for the colonisation since the Old Stone Age. Firstly the Paleolithic man found there his house – a karst caves within the Jurassic limestones (now the Dragon Cave is a show cave under the King Castle in the Wawel Hill – Fig. 11). But he and his ancestors during the New Stone Age, Iron and Bronze Epochs as well as in the Middle Ages were also naturally defended by rivers and swamps from enemies and plunderers. Besides, the population of the Wawel Hill did not suffer hunger. When the year was rainy, the farmers harvested good crop on the top of the hill, but when the soil on the hill was hard and dry, wanting the water, the crops were pretty good on the swampy fields on the river. And the rivers must have swarmed in fish independently of human activity. Vistula river was also very convenient way of communication, trade and transport before the trains and cars were invented.
So, therefore the decision to settle and live on the Wawel Hill seemed to be obvious for every reasonable people, which came here in the historical time. And these conditions favourable for human live were stimulated by the lithology of the Jurassic rocks, Neogene tectonic processes and fluvial activity of proto-Vistula River in the Pleistocene (the older epoch of the Quaternary). Therefore, the Wawel Hill and Kraków town is one of the most apparent examples of the everlasting interconnections between man and nature, especially inanimate nature.
Fig. 1. Romanesque Saint Andreas church.
Fig. 2. Gothic Saint Mary church and the Renaissance buildings in the west side of the Central Square.
Fig. 3. Baroque Saint Peter and Paul church.
Fig. 4. North-western part of the Old City with the Saint Cross Church in Gothic style Słowacki Theatre and the Słowacki Theatre built in the second half of the 19th century.
Fig. 5. The central square with the Renaissance “supermarket”.
Fig. 6. Saint Florian Church in Baroque style and Academy of Art.
Fig. 7. Central Square and the Saint Anna Church of the Jagiellonian University behind the Renaissance “supermarket”. In the background the hills being the uplifted tectonic blocks formed of the Jurassic limestones
Fig. 8. King Castle on the Wawel Hill above the Old City.
Fig. 9. King Castle on the Wawel Hill above Vistula River.
Fig. 10. Geological structure of the Wawel Hill.
Fig. 11. Smocza Jama (Dragon Cave) within the Jurassic limestone of the Wawel Hill.
PS: Many thanks to dr Jan Urban for great article and photos.