Looking outside of the map

From Glitches

From the game Tales of Symphonia for the Nintendo Gamecube

Go to Fooji mountains at any point of the game. Now, near the entrance you should see a large rock (there is a treasure chest behind it). Walk behind it, and hug the wall. At the top right corner of the screen, you should see untinted blue, showing that it isn't supposed to be there. This happens because the background to every map is blue.