This is the final fortress in Super Mario Bros. 3. This fortress is also one of the toughest levels in the game. The fortress is filled with many doors leading to two different parts of the fortress. Enemies such as Dry Bones and Boos inhabit it. Roto Discs also appear and fly around the hub they are connected to. There are many power ups and dangers. The recommended path on the image on the screen will help get through the fortress just click on the image twice. The best path begins by going through door D. When going through the door and appearing over the lava, run all the way to the right. Avoid the Thwomp at door H and continue running in the gray room. Grab the Super Leaf and continue to the right past the lava. Continue past door J in the gray area. Bust the wall with the raccoon tail and continue. Make it to door O and continue to the conveyor belt. Jump to the bottom floor underneath the conveyor belt avoiding the Thwomp and hit the second block revealing a P switch. Jump back on top of the conveyor belt and run to the right and go into door S and duck beneath the spikes on the conveyor belt. Defeat Boom Boom.