Object: The Master Sword
Recovered: throughout the series
Appearance: Skyward Sword, Ocarina of Time, A Link to the Past, Twilight Princess, Wind Waker, Oracle of Ages/Seasons
The Master Sword has a peculiar aura about it: the blade of evil's bane cannot be touched by evil. The only person who can actually wield the blade would be the Goddesses chosen hero. According to legend, the sword was crafted by the ancient sages (according to legend) to repel evil. The Master Sword was created from the Goddess Sword. The Goddess Sword was an instrument created by the goddess Hylia to be used to combat evil. Should Demise (or according to legend, a powerful evil force) reincarnate, this weapon would become necessary.
Early in it's history, the Master Sword served as both a weapon against evil and as a key for time travel. After the events of Skyward Sword, many evil hearts somehow penetrated the Sacred Realm in their quest for the Triforce. When the sages noticed this, Rauru, the sage of light constructed the Temple of Time allegedly over the ruins of the sealed grounds in order to protect the Triforce. Since the Master Sword is so powerful, and can act as a key- it was a natural choice for protecting the only way to the sacred realm.
The sword was stored in the Sealed Grounds (old Temple of Hylia) and later in the Temple of Time (rumored to be built on the Sealed Grounds), guarded by an altar and the Door of Time. The Master Sword acts as more than just a weapon: it is the key that allows the wielder to access the Temple of Light, where the Triforce is located. The Temple of Time is merely train station A to get to the triforce at station B. The only weapons strong enough to defeat Ganon are the silver arrows and the Master Sword. In official canon, in the Japanese manual of A Link to the Past, the Master Sword was created long before the Imprisoning War. We now know that the Master Sword had its origins with the goddess Hylia and the goddess sword.
Before its transformation into the Master Sword, the Skyward Sword rested in Skyloft as the Goddess Sword. Fi, a spirit created by Hylia is the sole resident of the Goddess Sword and is the eventual spirit of the Master Sword. The blade is so powerful that it is able to cure curses and break dark magic spells. Later, in the Wind Waker universe, sages are required to power up the Master Sword after its power had waned over the course of 150 some years. This loss of power does not occur in every parallel universe, but it is hinted by the King of Red Lions that the maintenance of the blade's power is maintained by two additional sages: the Sage of Wind and Sage of Earth.
In Ocarina of Time, Link attempted to pull the sword out of the pedestal of time and succeeded. The spirit of the sword, Fi will always determine it's owner by resonating with them and requiring them to undergo challenging trials. This is why Link was sealed away for seven years before the sword could feel that he is ready. During this time, Ganondorf roams about for seven years causing the mayhem in the Adult timeline. The sword can also seal an evil being if the blade is left impaled in them.
Later, in titles such as A Link to the Past and Twilight Princess, the blade remains forgotten in the Pedestal, surrounded by the ruins of the old Temple of Time. The way to the Temple of Light was closed long ago in these titles. Over the course of
WARNING: THE FOLLOWING INFORMATION IS NOT CANON
According to the Skyward Sword manga, the Master Sword was indeed forged by a band of courageous heroes who could be called sages. This manga blurs the line between the Goddess Sword and the Master Sword. The sword was given to a knight of Hylia, Link by the Goddess Hylia. When the sword, which could only be used by a God was touched by a human, it shattered. It was reforged and its power reinvigorated by the spirit of Link and the goddess herself. With the weapon, Hylia sundered the earth of many demons.
The Master Sword acted as a pillar to raise Skyloft up into the air. Hidden in Skyloft was an entrance to the Sacred Realm where the Triforce stayed. To protect it, Hylia sent up the plot of land into the sky along with the inhabitants of the kingdom. It was on that piece of land that Skyloft was formed. Before Hylia sacrificed her divinity to seal Demise, the sky was protected with a barrier that would keep evil out.
It is unclear after the Master Sword acts as the center pillar to lift Skyloft as to what actually happens to the blade. We do know however, that, according to the manga, the Master Sword became the Goddess sword with a resident spirit, created by Hylia, to guide the hero to the blade in times of danger.
If the manga is correct, it could then be argued that if the Master Sword lifted Skyloft into the air by creating a pillar that the Pedastal of Time is directly on or located near the point where the pillar was made.
The source of some of this information in the article was from Zelda Wiki, the games themselves and Hyrule Historia. I will come back again when I get the full copy of Hyrule Historia to add more relevant information, if it exists. It is important to note that although I believe Zelda Wiki is correct and great in many respects, I believe some of the information is inaccurate, wrong or has weak evidence.