Grand Temple Key

The Grand Temple Key was an amulet-like Piece of Eden that functioned primarily as a key to the inner sanctum of the Grand Temple in New York.

In 1754, the key was in the possession of the Assassin Miko. On the orders of Templar Grand Master Reginald Birch, Haytham Kenway assassinated the man inside the in London and took the key from him. Upon Haytham's return to the Templar headquarters, Birch told Haytham that the key most likely opened a First Civilization storehouse in the British colonies. As a result, Birch booked Haytham passage to Boston, in order to find it and unlock its contents, and to establish a permanent Templar presence in colonial America.

In 1755, Haytham, with the help of his Mohawk ally Kaniehtí:io, located the entrance to the Grand Temple, but they were unable to access it, as he did not possess an Apple of Eden to open the first door. Following this, Haytham kept the amulet in his possession until 1781, when he passed it on to his second-in-command, Charles Lee.

In the following year, the Assassin Ratonhnhaké:ton, Haytham's son, killed Charles Lee in Boston and took the amulet from him. He later returned to his Mohawk village of Kanatahséton where he activated his tribe's Crystal Ball he used years earlier to communicate with Juno. Juno greeted Ratonhnhaké:ton again, and told him to hide the amulet where none might find it. Following this, he made his way back to the manor at the Davenport Homestead and hid the key in the grave of Connor Davenport, after whom Ratonhnhaké:ton's mentor Achilles Davenport nicknamed him.

In 2012, Ratonhnhaké:ton's descendant Desmond Miles relived his memories inside the Animus and found out where the key was hidden. After having retrieved it, Desmond used it to open the gate in the Grand Temple.

Reference

 * Assassin's Creed III