The Berggarten is an important European botanical garden.[citation needed] Some points of interest are the Tropical House, the Cactus House, the Canary House and the Orchid House, which hosts one of the world's biggest collection of orchids, and free-flying birds and butterflies. Near the entrance to the Berggarten is the historic Library Pavillon. The Mausoleum of the Guelphs is also located in the Berggarten. Like the Great Garden, the Berggarten also consists of several parts, for example the Paradies and the Prairie Garden. There is also the Sea Life Centre Hanover, which is the first tropical aquarium in Germany.[citation needed]