Opened in 1899, the The Cimetière des Chiens et Autres Animaux Domestiques is the oldest pet cemetery in Europe, and perhaps the world, depending on your definition of a "pet cemetery."
The grave of Rin Tin Tin is here, along with a race horse and a menagerie of other pets. Just past the entrance is a monument to Barry the Saint Bernard, a famed rescue dog. Obviously, some graves are more famous than others, but it's safe to say that each belongs to an animal who had a very loving family.
To this day, many of the tombs are decorated with dog toys, with some of them permanently affixed to the tombstones. The stone entrance was designed by Art Nouveau architect Eugene Petit and can be easily seen as you cross the Seine.
Instead of mausoleums, many of the tombs are stone dog houses. There is a house at the back of the cemetery when they take care of stray cats.
A small entrance fee is payed at the gate, and then you are free to wander the tombs.