This is one of the famous and most beautiful drainpipes in Paris. It can be seen at the Hotel de Lauzun at 17 quai d'Anjou on Île Saint-Louis in the 4th arrondissement. (N.B. No, you can't book a room here).
The hotel was supposed to have been the centre of evil, the headquarters of a satanic federation in the movie The 9th Gate directed by Roman Polanski starring Johnny Depp.