Tulln an der Donau (Tulln on the Danube) is a town in the Austrian state of Lower Austria, and the seat of the Tulln district. Because of its abundance of parks and other green spaces, Tulln is often referred to as Blumenstadt, meaning city of flowers. While the town is surrounded by the Tullnerfeld flatland, almost all of its built-up area is located on the southern bank of the Danube.