The Warsaw Zoological Garden, known simply as the Warsaw Zoo (Polish: Warszawskie Zoo), is a scientific zoo located alongside the Vistula River in Warsaw, Poland. The zoo covers about 40 hectares (99 acres) in central Warsaw, and sees around 1,000,000 visitors annually, making it one of the busiest zoos in Europe. It is home to over 4,200 animals representing more than 500 species. The zoo is an accredited member of the European Association of Zoos and Aquaria (EAZA) and the World Association of Zoos and Aquariums (WAZA). Warsaw zoo is also famous for having hid 300 Jews being hunted for extermination by the Nazis during the Holocaust. Jan Żabiński, the director, together with his wife Antonina and their son Ryszard, risked their lives to save the Jews.