The Deliblato Sands is a geo-morphological formation of eolian origin, of exceptional specific beauty and multiple scientific importance. It is of diluvial origin. It is an isolated complex of sand masses with a distinctly undulating dune relief on an area of over 380 sq. kilometres, of elongated ellipsoid shape, surrounded by the expanses of the cultured steppe of the Pannonian plain. The dunes of yellow and gray sand with maximum elevations of around 200 metres above sea level (Pluc - 192 m; Crni vrh - 189 m.) stretch in a straight southesst-northwest direction like the whole complex of the Sands.The physical properties of the sand and soil are behind this areats specific hydrology and meso-climate. There are no sueface watercourses and the only hydrological facilities are dug and drillad wells (some thirty of them), from 100-400 metres deep, and three permanent natural waterholes in smaller depressions in the south-eastern part. The masses of the windblown sand of what used to be the "European Sahara" are today mainly tied down by vegetation, restored by man in planned fashion during the past 170 years. About 16,000 ha is under forest - mainly cultivated pure stands of Scotch and black pine, black locust, poplar,etc., and somewhat less under mixed stands of linden, English and pubescent oak, poplar, flowering ash, and other species. In addition to the anthropogenic forests, in the Deliblato Sands there are smaller preserved remains of one time autochthonous forests of English oak with linden and Lily-of-the-valley (Convalaria majalis).The specific and extreme ecological conditions of these habitats.