Four Sword Sanctuary

From Zelda Wiki.org

The Four Sword Sanctuary is the final resting place of the Four Sword. Legend states that a hero used this blade to vanquish Vaati, and sealed him inside the blade. Anyone who draws the blade, will be split into four, and release Vaati into the world. It can be seen housing the four elements that were forged into the Picori Blade, and is also the entrance to the Realm of the Heavens. In Four Swords Adventures, Shadow Link forces you to draw the blade. The six Maidens can be seen sealing away Vaati here.