London Zoo is the world's oldest scientific zoo.[5] It was opened in London on 27 April 1828, and was originally intended to be used as a collection for scientific study. In 1832 the animals of the Tower of London menagerie were transferred to the zoo's collection. It was eventually opened to the public in 1847.[5] Today it houses a collection of 698 species of animals, with 20,166 individuals, making it one of the largest collections in the United Kingdom.[7] The zoo is sometimes called Regent's Zoo.

It is managed under the aegis of the Zoological Society of London (established in 1826), and is situated at the northern edge of Regent's Park, on the boundary line between the City of Westminster and the borough of Camden (the Regent's Canal runs through it).[8] The Society also has a more spacious site at ZSL Whipsnade Zoo in Bedfordshire to which the larger animals such as elephants and rhinos have been moved.[9][10] As well as being the first scientific zoo, ZSL London Zoo also opened the first Reptile house (1849), first public Aquarium (1853), first insect house (1881) and the first children's zoo (1938).

ZSL receives no state funding and relies on 'Fellows' and 'Friends' memberships, entrance fees and sponsorship to generate income