Vienna basin

The Vienna Basin (German: Wiener Becken, Czech: Vídeňská pánev, Slovak: Viedenská kotlina) is a sedimentary basin between the Eastern Alps and the Carpathian Mountains.

The fairly level area has the shape of a spindle, over an area of 50 km (31 mi) by 200 km (120 mi). In the north it stretches up to the Marchfeld plateau beyond the Danube River. In the southeast, the Leitha Mountains separate it from the Little Hungarian Plain. In the west, it borders on the Gutenstein Alps and Vienna Woods mountain ranges of the Northern Limestone Alps. The Danube enters the basin at the Vienna Gate water gap near Mt. Leopoldsberg, it leaves at Devín Gate in the Little Carpathians east of Hainburg.

From the late 12th century onwards, the fortresses of Wiener Neustadt and Hainburg were erected at the southeastern and eastern rim as a defensive wall against attacks from the Hungarian lands downstream the Danube River. Nevertheless, the forces of King Matthias Corvinus entered the Vienna Basin during the Austrian-Hungarian War in 1485 to begin the Siege of Vienna. It was again invaded by Ottoman troops, who besieged the city in 1529 and 1683.

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