The region Lake Neusiedl/Fertő is a cross border landscape, unique in the world. The area around Lake Neusiedl/Fertő and that of the Hungarian Hanság, with the still existing areas of the formerly huge swamp and marsh-land, is a rare island of nature at the meeting-point of the two countries. The lake is the third largest standing water of Central Europe, its age is estimated at some 20 thousand years. Its length is 35 kilometres, width 7-15 kilometres, its surface area is 315 km², three quarters of it are in Austria, the Hungarian area is approximately 75 km². Its catchment area is 1,230 km², which is four times bigger than the lake itself. The natural water management of Lake Neusiedl/Fertő is mostly depending on precipitation and evaporation, influx and discharge are neglectable Water supply is provided through two streams, the lake does not have a natural outflow; its water can be let out only in an artificial way, through Hanság Channel, by opening the lock gate. The lake is characterised by shallow water, the great extent of the fluctuation of the water level, and the mild salt contents. The Southern (Hungarian) side of the lake is 80% taken up by reeds, in places its width reaches 5-6 kilometres; this zone of reeds provides the characteristic shape of the appearance of the lake, and it furthermore has a decisive affect on the water balance and the water quality of the lake.
The region around Lake Neusiedl/Fertő has a unique significance from the aspect of fauna and flora, the landscape, ethnography and the history of culture. From the ornithological point of view the area of Lake Neusiedl/Fertő is one of the most remarkable sites in Europe. More than 300 species of birds (150 of them breeding in the region), including many rare and endangered species, were observed.
In Austria the region consists of the Lake Neusiedl/Fertő and its reed belt and Western foreground terrain and the so–called Seewinkel. Salty ponds (“Lacken”) without any water contributor or drain with a depth of approximately 0.5 metres are characteristic for the Seewinkel.
On Austrian territory there are a landscape protection area, five nature protection areas, a protected habitat and the National Park Neusiedler See–Seewinkel. International appreciation was attained with the declaration as a Biosphere Reserve of the UNESCO, as protected area of the RAMSAR–convention, as an European Biogenetic Reserve and as a national park of the IUCN (International Union for Conservation of Nature and Natural Resources) category II. Furthermore, the region was declared as World Cultural Heritage by UNESCO and nominated as a protected area of the EU–Birdprotection and Habitat directives.
The joint opening of Lake Fertő National Park, which was established in Hungary in 1991 and was alled so in that time, and of the Austrian National Park, established in 1992 with an area of 9500 hectare took place in April 1994. Thus, the total area of the national parks forming a single ecological unit exceeds 33 thousand hectares. Its Hungarian part is 23.6 thousand hectares, which also contains the areas lying farther away from Lake Neusiedl/Fertő.
The so-called Fertõ land with a territory of approx. 12.5 thousand hectare can be considered an adjoining
area.
The geographical location of Lake Neusiedl/Fertő, as well as the international obligations, poses common
tasks for the two countries. In course of their activities, the Hungarian and Austrian national parks and water management agencies work together in organised forms. The joint activity was the reason for the co-ordinated audit by the supreme audit institutions of the two countries.
The audits were regularity audits as well as performance audits, focusing on the efficiency and effectiveness
of resources spent, and ecological issues of already implemented and planned programmes and measures. Intention of the audit was to reveal conflicts in the use of the region, to elaborate possibilities to solve them and to evaluate the bilateral co-operation.