Flows through the city from the west to the east, below Kraków turns north-east. Flowing through the eastern end of the Grzbiet Tęczyński , it creates a amazing ravine. During a low water level, 26 cubic meters of water flow down the Vistula per second, during an average state of 70 cubic meters, during a high state of 850 cubic meters. The water it carries is completely polluted. The name Vistula appears already in the Chronicles of Gallus Anonymus, in the document of Konrad from 1224, which gave the monastery beavers, the name “in Visla” appears. The name appears for the first time in 7 years on the map of M. Vipsanius Agrippa, displayed to the public in the portico on the Capitoline Hill in Rome. The oldest Vistula riverbed ran along a route similar to today’s one. However, in order to increase the city’s defenses, construction began already in the 13th century, and under King Casimir the Great, an artificial 2 km-long bed between Stradom and Kazimierz was completed – now Planty Dietlowskie al. Daszyński. The main stream of the Vistula River was blocked by a stone dam through the Skałka river, and in this way the river waters were directed into an artificial riverbed. Thanks to this, Kazimierz was – like an island – flooded with water on all sides, as the dam allowed some of the water into which the Wilga fell, creating a river called Zakaźmierka. Unfortunately, numerous floods, as well as the weakening of the walls of the dam due to the building of a mill on it, resulted in larger and larger gaps in the dam, and finally it collapsed in 1571. The Vistula was of great economic importance in the interior of the country, salt, wood, grain and others were transported. In Chronicles by Jan Długosz mentions an artificial canal 40 km long connecting Bochnia and the Vistula, built to facilitate the transport of salt. Coal for Krakow was transported from Silesia along the Vistula. In the past, the port was located between Na Groblach Square and Dębniki.