London Zoo has released old maps of its Regent's Park site dating back to 1928.
The documents were added this month to the 'Time Travelling guide to London Zoo' which can be found on their website.
They tell the story of the world's oldest scientific zoo and its architectural milestones, with links to learn about events, people and the animals who have lived there.
Those interested in the zoo's architectural heritage can dig deeper into the design and uses for each major building, and there's a fun quiz to test your knowledge of the iconic attraction.
The Zoo was founded in 1826 and by 1828 had established a 'zoological garden' in Regent's Park with aviaries and animal paddocks.
It became home to the world's first reptile house in 1849, and public aquarium in 1853. Charles Darwin himself recorded how a puff adder made him jump after he pressed his face against the glass.
There are several listed buildings at London Zoo including the modernist Grade I listed Penguin Pool designed by Berthold Lubetkin which is no longer used as an enclosure, and his Round House which was originally built for monkeys but now houses bats.
The Grade II listed Mappin Terraces were built in 1913-1914 as concrete mountains designed to create a naturalistic setting for bears and deer. Winipeg, the brown bear that inspired Winnie-the-Pooh lived in the part of the terraces where the wallabies live today.
The Grade II* Snowdon Aviary opened in 1965 as the first walk through bird enclosure, and has now been repurposed for a troop of Colobus monkeys.
As larger animals were moved to ZSL's sister site in Whipsnade, and new enclosures were built offering improved animal welfare, the Zoo's Giraffe house is the only Victorian building still being used for its original purpose.
Designed by the Zoo's original architect Decimus Burton, it was built in 1837 to house the four animals shipped from Sudan the year before. With no other means of getting them from Blackwall docks to Regent's Park, Selim, Mabrouk, Guib-allah and Zaida were walked through London accompanied by a Police escort to keep the roads clear.
In 1940, a World War II bomb damaged the west part of the Giraffe House and the zebra wing. One of the zebras escaped, but was rounded up later in Camden Town.
Other famous Zoo residents include Jumbo the elephant who arrived in 1865 and made his name synonymous with being big. He gave rides to visitors and grew to 11 foot tall by the 1880s when he was sold to showman PT Barnum who toured him around America. He died in a railway accident and his skeleton is held by New York's Museum of Natural History.
When Obaysch arrived in 1850, he was the first hippo seen in Europe since Roman times and was visited by Queen Victoria herself.
And Guy the gorilla who arrived on Guy Fawkes day 1947, became a firm favourite with visitors until his death in 1978 of a heart attack while having a tooth extracted.
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