The Berlin Zoological Garden is the oldest and best-known zoo in Germany. Opened in 1844, it covers 35 hectares (86.5 acres) and is located in Berlin's Tiergarten. With about 1,380 different species and over 20,200 animals, the zoo presents the most comprehensive collections of species in the world.
The zoo and its aquarium had more than 3.5 million visitors in 2017. It is the most-visited zoo in Europe and one of the most popular worldwide. Regular animal feedings are among its most famous attractions. Globally known animals like Knut, the polar bear, and Bao Bao, the giant panda have contributed to the zoo's public image.
The zoo collaborates with many universities, research institutes, and other zoos around the world. It maintains and promotes European breeding programmes, helps safeguard several endangered species, and participates in several species reintroduction programs.
According to en.wikipedia