The Botanical Garden adjoins the Belvedere park. Established in 1754 under Empress Maria Theresa, it is now an independent division of the University of Vienna. The expansive grounds include open spaces and greenhouses and are home to thousands of species including medicinal plants, which were the foundation of the garden originally. The special collections containing orchids, succulents, and Pannonian plants are of great importance for species conservation and biodiversity research. The Botanical Garden, the Schweizergarten, and the parks of the Belvedere and the Palais Schwarzenberg form Vienna’s largest inner-city green space.