Stone Tower

In Majora's Mask, the Stone Tower is a mysterious tower located at the northern edge of Termina's Ikana Canyon. It is filled with a large chasm, blocks, and pressure switches. Boulders constantly fall here, making the climb to the top a hazardous one. Guarding the chasm are Fire Keese and several Beamos.

Only with the Elegy of Emptiness is Link able to scale the chasm and reach the top, coming to face the Stone Tower Temple. At the base of the temple, a curious red gem can be found, that when struck with the Light Arrow, possesses the power to completely flip everything inside the chasm upside down. Curiously, this does not affect the rest of Termina in any way.

Origins
The origins of these towers are mysterious, but there's a hypothesis that may help to clear things up.

Trivia

 * Closer observation to the dungeon map reveals that when the red gem is hit, Stone Tower Temple not only flips upside down, it does, in fact, mirror itself as well.
 * Near the entrance to the Stone Tower Temple, there is a near inaccessible ledge that supports three Redeads which do not move, and give red Rupees when defeated. Twelve Jars that contain fairies and small amounts of magic can also be found here.