In this Warp Pipe is a secret underground section, containing a room with a massive Brick Block ceiling and a row of coins leading to a Warp Pipe. Beside this is a set of seven Brick Blocks, leftmost being a Coin Block, over a Warp Pipe with a Little Goomba. Past this is a set of four Brick Blocks, with the middle-left Brick Block containing a Starman. After this is another pit and two Little Goombas, along with a Koopa Troopa stuck between two Warp Pipes. A Hidden Block is hidden under these Brick Blocks, which helps the player get a hidden 1 up Mushroom which to the right of the leftmost Brick Block. To the right of this is a pit and a set of five Brick Blocks with two green Koopa Troopas on top of them. The leftmost ? Block contains a Magic Mushroom or Fire Flower.

After a Warp Pipe and a staircase made of Hard Blocks, there will be a set of three Brick Blocks with a set of three ? Blocks over them. Following these are three ? Blocks, all containing coins, which is proceeded by two green Koopa Troopas. After this is a Little Goomba and two green Koopa Troopas beside a Warp Pipe next to a bottomless pit. World 1-1 starts off with an empty plain followed by a ? Block containing a Magic Mushroom or Fire Flower.

Super mario bros. world 1-1 layout