You need the Goron to do this. You can actually go over short walls such as the one blocking the path to Great Bay, the one blocking entry to the Gorman Race Track, the one blocking entry to the Great Bay Spider House, and many other places. Go up to the wall you want to jump over with the Goron, plant a bomb behind you, wait until the bomb is about to explode, then do the goron pound (hold down A and hit B). As soon as Goron Link bounces into the air, let go of A. If timed correctly, the bomb will explode just as you are in the air, blasting you over the wall. You can use this to get to Great Bay early; you can use this to enter the Gorman Brother Race Track and walk around it as Link rather than Epona; you can use this to go over the gate in the Great Bay Spider House without the hookshot; you can use this in countless areas in Temples, and many other places.