|Spoiler Alert! This section describes a subject that is sensitive to plot development.|
This is Sky Keep. It is situated beneath
The Sky Keep is the seventh and final dungeon in Skyward Sword. The dungeon itself is located in Skyloft, but it can only be entered after Link completes the Song of the Hero quest, creating the bottom half of Skyloft to fall down, revealing the Sky Keep.
The main focus of the Sky Keep is to find and collect the three pieces of the Triforce, which are hidden somewhere in the dungeon each in their own Sacred Realm. Since the Triforce is such a powerful item, it is heavily protected and is not easy to collect. The design of the temple is made up of squares, with each square being a different setting or pace that Link has visited on his journey so far. In certain rooms are small stone blocks, and using those, Link can solve the puzzle of the temple and move the rooms around, making it possible to travel from one room to the next.
After Link collects all three pieces of the Triforce, he gets to make his wish; a wish for Demise to be vanquished. A cut-scene will occur where the Triforce is placed onto the Statue of the Goddess, which then falls down through the clouds, landing perfectly in the spiral shaped hole in the Sealed Grounds where The Imprisoned was just beginning to rise up from yet again. The force of the Goddess Statue Landing onto The Imprisoned finally rids the Surface of the threat of Demise, at least in the present time.
This dungeon technically has no boss, though it does have a few mini-bosses. After this dungeon, Link fights Ghirahim and Demise for the last time, making up for this dungeon's boss's absence.