The Bronx Zoo is a world-famous zoo located within the Bronx Park, in the Bronx borough of New York City. The largest metropolitan zoo in the United States, the Bronx Zoo comprises 265 acres of parklands and naturalistic habitats -- home to over 4,000 animals, many of which are endangered or threatened species. The zoo originally opened its doors to the public on November 8, 1899, featuring 843 animals in 22 exhibits, after being established by New York Zoological Society.