In the common room near the marble statue of Rowena Ravenclaw a tapestry of a beautiful, singing mermaid hangs. The mermaid guards the entrance to a secret room full of books and other treasures. To get past the mermaid you need to use your wits to charm her to allow you entrance. An easy feat one should think for witty young eagles? When you gain access to the room you'll be faced with a maze riddled from floor to ceiling with bookshelves.
Why don't you go and explore and see what treasures you can find? Beware of sleeping trolls and wombats!!!!