World 1 (Super Mario Bros.)

World 1 is the first world in the game Super Mario Bros., located in the Mushroom Kingdom. It is set on a grassland with many bushes, hills and trees inhabited mainly by Little Goombas and Koopa Troopas.

Enemies introduced

 * Little Goomba
 * Koopa Troopa
 * Piranha Plant
 * Koopa Paratroopa
 * Fire-Bar
 * Fake Bowser (boss)

Trivia

 * Several sections of Lineland Road in Super Paper Mario are modeled after those of World 1-1. Also in Super Paper Mario, in Chapter 3-1, there's an underground section almost identical to World 1-2, but the Warp Zone leads to other parts of the area, not other worlds.
 * All levels in this world were released as card levels for World-e in Super Mario Advance 4: Super Mario Bros. 3. However, only World 1-1 was released outside of Japan until the game was released for the Wii U Virtual Console, where all the World-e levels were available worldwide by default.
 * World 5-3 is the same as World 1-3 but with Bullet Bills added.
 * World 6-4 is the same as World 1-4 but with more Firebars and Podoboos.

Welt 1 (Super Mario Bros.) Mondo 1 (Super Mario Bros.)