Zoo Basel is a non-profit zoo located within the city of Basel, Switzerland. Its official name is Zoologischer Garten Basel — or in English: Basel Zoological Garden. Basel residents, however, call their zoo affectionately Zolli. Its main entrance is just outside of Basel's downtown strip of Steinen and extends in the Birsig stream valley to Basel's city border with Binningen, Basel-Country.
Zoo Basel is Switzerland's oldest (1874) and largest zoo (by number of animals). With nearly 1.7 million visitors per year, it is the most visited tourist attraction in Switzerland with an entrance fee.
Zoo Basel was ranked as one of the fifteen best zoos in the world by Forbes Travel in 2008, and in 2009 as the seventh best in Europe by Anthony Sheridan from the Zoological Society of London.
The zoo had the first Indian rhinoceros birth in a zoo, as well as the first Greater flamingo hatch. It has also had repeated breeding success with animals including cheetahs (18 births), okapi (22), Pygmy hippopotamuses (53), and flamingos (over 400 hatches). Every Somali Wild Ass (a donkey) in zoos worldwide is related to the population in Basel, where this species' zoological breeding program was started.