The Carpathian Basin or Pannonian Basin is a large sedimentary basin situated in southeastern Central Europe. After the Treaty of Trianon following World War I, the geomorphological term Pannonian Plain was also used for roughly the same region, referring to the lowlands in the area occupied by the Pannonian Sea during the Pliocene Epoch, the term "Pannonian Plain" being considered not only unhistorical but also topologically erroneous. From Wikipedia
