Prague Zoo is a zoo in Prague, Czech Republic. It was opened in 1931 with the goal to "advance the study of zoology, protect wildlife, and educate the public" in the district of Troja in the north of Prague. The zoo occupies 45 hectares (111 acres) and houses about 4,400 animals that represent 670 species from all around the World. Prague Zoological Garden has contributed significantly to saving the Przewalski horse. For many years it was the biggest breeder of the species in the world. In 2007 Forbes Traveler Magazine listed Prague ZOO among the world's best zoos.