Dike breaches in the Carpathian basin
Hungary is situated in the part of Europe drained by the Danube, in the deepest part of the hydrographic unit called the Carpathian Basin. Her territory covers 93000 km2 and represents 11.4\% of the 817 000 km2 large Danube catchment. The Carpathian Basin is bounded to the west by the 2000-3000 high ranges of the Alps, to the north and east by the Carpathian Range the peaks of which rise to over 1000-2000 m above sea level. In contrast thereto, 70\% of the territories are plains below 200 m, while hardly 1\% consists of hills higher than 500 m AMSL. The eastern parts of the country are the deepest, the lowlands here being between 80-100 m AMSL only. Owing to this topography, an area of round 21 200 km2, that is 23\% of the territory of Hungary is below the flood level of the rivers. This fact alone presents flood defence problems which are unique in Europe and comparable in order of magnitude perhaps to those in the Netherlands alone.