The Pittsburgh Zoo & Aquarium is a zoo and aquarium in the United States, one of only six major zoo and aquarium hybrids in the United States. Located in Pittsburgh, Pennsylvania's Highland Park, the zoo sits on 77 acres (31 ha) of park land where it exhibits more than 4,000 animals representing 475 species, including 20 threatened or endangered species.

Pittsburgh is a city in the Commonwealth of Pennsylvania and the county seat of Allegheny County. It is the second-most populous city in Pennsylvania after Philadelphia and the 68th-most populous city in the U.S., with a population of 302,971 as of the 2020 census. The city anchors the Pittsburgh metropolitan area of Western Pennsylvania. Its population of 2.457 million is the largest in both the Ohio Valley and Appalachia, the second-largest in Pennsylvania, the 7th-largest in the Mid-Atlantic region and the 26th-largest in the U.S. Pittsburgh is the principal city of the greater Pittsburgh–Weirton–Steubenville combined statistical area which includes parts of Ohio and West Virginia.