You used to be able to use a mount in the York tower cave and use it to glitch onto the unreachable part of the cliff by the door, then you could jump off it and it would warp you to an area above Snowtown and there was this huge area with buildings there.

Also back in 2013 you could get to the area which is now Destiny, you could use a mount to jump onto the cliff and then jump off and go right, then you could just go as far right as you could and you would end up in the water under pyrat bay under the dark blue solid water with a island cave that spawned bugs.