This article is about the Library of Shadow. For the Elven city referred to by a similar name, see Rivendell.
Non-Canon Alert! The subject of this article originates from non-canonical sources. To find out about what is considered "canon" see LOTR:Canon.
The Hidden Vale, named fully the Secret Library of Shadow and also called Raven Vale, was a secret remote place in Mordor at Barad-dûr's east in which Sauron established a great store of his secret knowledge, so that if the Dark Tower were to fall, his artifacts and documents might remain.