I'll upload images soon because i'm about to go to sleep but here's an glitch on snow valley where you can get off map or you could go elsewhere with the glitch and discover new things.
It's going to be kinda hard describing where to go since there's no images but here's the glitch.
1. Go to snow valley and head to the oil pipe line.
2. Go to where the pipe line meets the most farthest part of the map.
3. where the pipe hits the wall there should be rock next to it stopping you from falling out of the map.
4. On the support beams that hold the pipe up rub up agianst them and slice at it crouch
5. You should eventually see through the map and you can fall through the map or either walk on the edge of the map and discover new places.
Credits.. Go to me for discovering this glitch
I'll try to get some images up so i can help you later.