Philadelphia Zoo

http://www.philadelphiazoo.org/

Like many other Philadelphia landmarks and institutions, the Philadelphia Zoo is an American first. The charter establishing the Zoological Society of Philadelphia was approved and signed on March 21, 1859. Due to the Civil War, however, it was another 15 years before America's first zoo was ready to open.

In its first year of operation, the Philadelphia Zoo had 813 animals and received well over 228,000 visitors. Today, the Zoo has more than 1,300 rare and endangered animals, and its attendance is approximately 1.1 million visitors a year.