World 4-1 (Super Mario Bros.) - Super Mario Wiki, the Mario encyclopedia

World 4-1 is the first level of World 4 in Super Mario Bros. and the thirteenth level overall in said game. This level introduces the Lakitu and Spiny enemies in the series.

World 3-1 (Super Mario Bros.) - Super Mario Wiki, the Mario encyclopedia

World 1-1 (Super Mario Bros. 2) - Super Mario Wiki, the Mario encyclopedia

World 4-Fortress 1 - Super Mario Wiki, the Mario encyclopedia

World 4-1 (New Super Mario Bros. Wii), MarioWiki

World 4-1 (New Super Mario Bros. 2) - Super Mario Wiki, the Mario encyclopedia

World 2-2 (Super Mario Bros.) - Super Mario Wiki, the Mario encyclopedia

New Super Mario Bros., Nintendo

World 8-1 (Super Mario Bros.) - Super Mario Wiki, the Mario encyclopedia

Super Mario Bros. 3, Nintendo

World 1-1 (Super Mario Bros.: The Lost Levels) - Super Mario Wiki, the Mario encyclopedia

World 5-2 (Super Mario Bros.) - Super Mario Wiki, the Mario encyclopedia