Castle Wall is the second track in the Bowser Cup from Mario Kart Arcade GP.
The track starts outside the castle, in the same place as in Bowser's Castle. The hallway and first room here are also the same as before. Once outside the castle, you'll go up some stairs, and drive along a curved hall, with some rooms with glowing lights on the inside. You'll then exit an go across a metal bridge. The area after this goes along the wall, hence the name, then goes down some stairs, and takes you back to the finish line.