It is exactly 42 years on Christmas Eve since Biggie the giant tortoise arrived at Bristol Zoo.
He has been at the 181-year-old zoo longer than any other animal and is one of four giant Aldabra tortoises who live at the zoo.
Although his exact birth date is not known keepers believe he is more than 60 years old and he could be around for many years to come as Aldabra tortoises can live to more than 100 years old.
Adam Davis, senior keeper at Bristol Zoo, said: "Biggie is a favourite with so many of our visitors. Everyone seems to love the fact that he is so big but he is also a gentle giant. No-one could imagine Bristol Zoo without him."
Aldabra tortoises can weigh up to 250kg (39 stones) and are so big that they cannot withdraw their heads and legs completely into their shells.
But on the islands where they evolved they did not need to use their shells as protection, as there were no predators.
They get their name from the Aldabra Atoll off the coast of the Seychelles and live off tropical grassland.
In the wild they begin feeding early in the morning when it is cooler and when the dew is thick on the grass.
Giant tortoises were found on many islands in the western Indian Ocean, including Madagascar, but were driven to extinction through over-exploitation by an increasing number of settlers and European explorers.
Today the Aldabra giant tortoise is classified as Vulnerable on the International Union for the Conservation of Nature Red List of Threatened Species.