World 3 (Super Mario Bros.)

World 3 is the first world in the Super Mario Bros. to be set at nighttime. This world also introduces the Hammer Bros. This world consists of two ground levels, one level set at the heights, and one Castle.

Trivia

 * Though the world is set at night, no objects' colors are affected. As a result, in Hard Mode, the Buzzy Beetles are almost invisible.
 * This and World 6 are the only two worlds that are set completely at night.

Welt 3 (Super Mario Bros.) Mondo 3 (Super Mario Bros.)