The Zoological Society of London (ZSL) was founded in 1826 by Sir Stamford Raffles. London Zoo sometimes called Regent's Park Zoo was opened in 1828 originally as a place for scientific study of animals. It was decided to close the Royal Menagerie in the Tower of London in the 1830s and the surviving animals were transferred to London Zoo. Animals were also transferred as a result of the closure of the Windsor Park Menagerie. The zoo was opened to the public in 1847. It is the world's oldest scientific zoo.

Originally tropical animals were kept indoors, however when Dr Peter Chalmers Mitchell was appointed secretary of ZSL in 1902 he began reorganising the enclosures and let more animals live in the open air. He also came up with the idea of Whipsnade Zoo which opened in 1931. In the 1980s London Zoo got into financial difficulties and in 1991 it was announced that the zoo would close. After public protests and increased visitor numbers it was reprieved. Some of the larger animals like elephants and rhinos were transferred to Whipsnade. Today London Zoo houses a collection of 800 species of animals, with 19,000 individuals.