The first zoo in the United States was in Pennsylvania.The Philadelphia Zoo was chartered on March 21, 1859, but its opening was delayed by the Civil War.It finally opened its gates on July 1, 1874. At that time, there were 1,000 animals and an admission price of 25 cents.The Philadelphia Zoo was the leader in some other areas, as well:First successful orangutan and chimpanzee births in AmericaFirst zoo in the world to build an on-site animal care centerFirst Children's ZooThe zoo is now home to more than 1,700 animals and welcomes more than 1.3 million visitors each year.Here are some of the exhibits and the animals featured:African Plains: Ankole cattle, hippopotamus, reticulated giraffe, southern white rhinocerosBear Country: Andean bearBig Cat Falls: African lion, Amur tiger, pumaBird Valley: Caribbean flamingoKidZooU: Huacaya alpacaPECO Primate Preserve: Western lowland gorillaPenguin Point: Humboldt penguinRare Animal Conservation Center: Golden lion tamarin, Rodrigues fruit batReptile and Amphibian House: Galapagos tortoise, McCord's Box TurtleSouth End: CheetahWater is Life: Giant river otter, red panda