There are many hidden treasures in and around Disneyland Paris, and one of my favourites is the Thunder Mesa Riverboat.
Although it's too big to really be 'hidden', it is an attraction that is generally overlooked. Similar to it's sisters throughout the Disney Parks, this Riverboat winds around the River (Thunder Mesa, in this case), uncovering some interesting sights.
You can board the Riverboat near Phantom Manor, in Frontierland, at the Thunder Mesa Riverboat Landing. Shall we hop aboard to go for a little journey around the River and Big Thunder Mountain?