Mountains' Graveyard

is a mountainous region that contains the bones of many giant creatures. It is a secret hideout of Tobi. Inside it is a laboratory, where Tobi keeps a massive storage of eyes, as well where he transplanted Itachi's Sharingan into Sasuke. Also, the Demonic Statue of the Outer Path rests inside a room, though it can be summoned elsewhere if needed. Deeper inside the headquarters is where Tobi cultivated the cells of Hashirama Senju into a clone to access his powers, as well as to amplify the power of his army of White Zetsu clones.