Schonbrunn Zoo is the world's oldest zoo still in operation. A UNESCO World Heritage Site, this 17-hectare zoo was established in 1752 by Emperor Franz I Stephan of Lorraine as a private menagerie. Opened to the public in 1778, the zoo is currently home to over 600 animal species, including Siberian tigers, koalas, African elephants, meerkats, and endangered Austrian species.