While turtles and tortoises are known to have long live expectancies, this particular animal is just absurd. Adwaita was a giant tortoise who was originally owned by General Robert Clive of the East India Company.
Clive ended up committing suicide in 1774, and left his already 34-year-old tortoise behind. Adwaita was eventually brought to an Indian zoo in 1875 after having several different owners, and spent the rest of his life there.
He survived until 2006, at which time scientists carbon dated his shell to around the year 1750! This makes him around 255 years old, which is a generation older than the United States, and means he was born before Mozart, Lincoln, and the French Revolution!