Sacred Realm

The Sacred Realm, also known as the Golden Land, is a holy world connected to the land of Hyrule, said to be the resting place of the Triforce. The three Golden Goddesses, Din, Nayru, and Farore, respectively, once they finished the creation of the land of Hyrule and its inhabitants, left behind a symbol of their strength, the Triforce, before departing for the heavens. The land where they left behind the golden power was said to be the Sacred Realm. The realm is said to be of twilight golden skies rather than the blue of Hyrule.
  The Golden Goddesses left the omnipotent Triforce under the protection of the Goddess Hylia. During the Era of Chaos, the Temple of Light, located at the center of the Sacred Realm, became the resting place of the Triforce, and was isolated from Hyrule, with the Temple of Time being the only entrance, as seen in Ocarina of Time.
  The Sacred Realm would serve as a mirror to reflect the heart of any who would enter it and come to claim the Triforce as their own. If that person's heart was pure, the realm would become a paradise. However, if that person's heart was wicked, the Sacred Realm would become a world of evil and the Triforce itself also splits apart into three separate pieces. It is thought that if another challenges and defeat the one who shattered the Triforce, the Sacred Realm and the golden relic would both return to its former beauty.
  The Sages and the Royal Family of Hyrule protect the Sacred Realm from the forces of evil.
  Due to the aforementioned feats, like the Triforce, the Sacred Realm plays a very important role in The Legend of Zelda series and it is one of Princess Zelda and Link's main objectives to defend it from evil, specifically their archenemy Ganon.