The Danube Delta is the second largest river delta in Europe, after the Volga Delta, and is the best preserved on the continent. As a young region in full process of consolidation, the Danube Delta represents a very favourable place for the development of highly diverse flora and fauna, unique in Europe. It hosts 23 natural ecosystems, but due to the extent of wetlands an aquatic environment is prevalent; a terrestrial environment is also present on the higher grounds of the continental levees, where xerophile ecosystems have developed.