The Philadelphia Zoo, located in the Centennial District of Philadelphia, Pennsylvania, was the first zoo in the United States. Its opening was delayed by the American Civil War until July 1st 1874.. For a brief time, the zoo also housed animals brought over from safari on behalf of the Smithsonian Institution, which had not yet built the National Zoo in the 1850s. The zoo is 42 acres (17 ha) and is home to more than 1,300 animals, many of which are rare and endangered. Bamboo I was the first gorilla imported to Philadelphia Zoo. He was a one year old male imported directly from Africa on August 5th 1927. The first gorilla birth at this zoo was unsuccesfull, when Snickers had a male baby in June 1975. He died due to a trauma during birth.
The PECO Primate Reserve was opened in July 1999 and is a pavilion where ten primate species are hold, including the zoo's gorillas. The outdoor enclosure consists on a grassy yard provided with hammocks and trunks as enrichment elements. The plants, located at the center of the exhibit, are surrounded by electric fence. There is also an indoor enclosure (used on cold days) and six bedrooms which are downstairs, under it.