Nestled amidst the scenic Ikana Canyon, Stone Tower Temple is home to the fourth and final Masked Boss, and is the last of the main dungeons in The Legend of Zelda: Majora's Mask.
In several instances, the entire structure of the temple re-aligns itself from a normal position to being completely inverted, with several puzzles hinting on this mechanic. The temple is also unique in comparison to the three preceding dungeons, in that it requires Link to utilize all of his transformation forms (Human, Deku Scrub, Zora, and Goron) to complete certain events.
There are two powerful weapons and one important mask obtainable in this dungeon -- the Light Arrows, the Great Fairy's Sword, and the Giant's Mask respectively, with the Light Arrows in particular being a very important tool for completing the dungeon (as they are used to invert the temple on multiple occasions).
The dungeon's boss is a fearsome pair of monstrous and towering worms, known as Twinmold; equipping the Giant's Mask, however, will cause Link become a juggernaut himself -- evening the playing field substantially.