Vienna Basin

Although it topographically separates the Alps from the Western Carpathians, it connects them geologically via corresponding rocks underground.

The Danube enters the basin at the Vienna Gate water gap near Mt.

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.

It is situated on top of the Alpine fold and thrust belt, located at the junction between the Eastern Alps, the Carpathians, and the Pannonian Basin system.

[3][4] The basin has been studied intensively starting with classical paleontological–stratigraphical papers and then continuing since the beginning of hydrocarbon exploration more than 100 years ago.