Dark Land

Dark Land is the eigth and last world in Super Mario Bros. 3. You can cheat to get here from World 1 by using two Warp Whistles. It was where Bowser's castle was in Super Mario Bros. 3 and probably still is now. It's called Dark Land because the sun doesn't appear between the volcanos clouds, and one of the areas is completly black on the map, except for a circle around Mario.