World B-1

World B-1 is the first level of World B in Super Mario Bros.: The Lost Levels and the ninth secret level overall in said game.

Layout
The player starts facing a couple of Goombas and a Koopa Troopa below a row of ? Blocks. Between the two pipes with Piranha Plants and another Koopa Troopa is a Hidden Block with a 1-Up Mushroom, and in the right-most block in the row of Brick Blocks ahead is a Coin Block. In the right-most ? Block above two Koopa Paratroopas is a power-up. To reach a Beanstalk that leads to Coin Heaven, the player has to hit two Hidden Blocks directly to the right of the pipe with a Piranha Plant, and break the Brick Blocks while in Super form. Coin Heaven will drop the player directly after the pipe on top of ? Blocks positioned afterward. In the center of the top row of Brick Blocks is a Super Star, and in the right-most ? Block after the Super Spring (Springboard in All-Stars) is a power-up. In the center ? Block afterward is a Poison Mushroom, and after platforms with Koopa Troopas, Koopa Paratroopas, Piranha Plants, and Goombas is the Goal Pole.