The European rivers Mura, Drava and Danube form a 700 km long “green belt” connecting more than 800,000 ha of highly valuable natural and cultural landscapes in five countries (Austria, Slovenia, Croatia, Hungary and Serbia). This area is a symbol of unity among the countries and is planned to become a protected Transboundary UNESCO Biosphere Reserve “Mura-Drava-Danube” (TBR MDD).