Ganon's Tower Clip

Similar to the Hera Clip , it is possible to clip into Ganon's Tower without opening the entrance.

Superspeed method

If you have the boots and the hookshot, it's very easy.

Line up with the top of the area where you are. Hold your sword then Hookdash.

Then move left in the edge until you can't.

Then fall with >v, after the fall press > to get unstuck (you will see link moving left), after than you can hookdash to swordclimb up.

If you don't have the Hookshot, you can still do it with multiple <+A inputs at the same vertical position.

Bunny Method

Pinkus made a guide found here.