World 6-6

World 6-6 may refer to:
 * World 6-6 in Super Mario Bros. 3.
 * The Deep, Underground Maze, World 6-6 in Super Mario World 2: Yoshi's Island.
 * World 6-6 in New Super Mario Bros..
 * World 6-6 in New Super Mario Bros. Wii.
 * Crumble Canyon, World 6-6 in Donkey Kong Country Returns.
 * Thrilling Spine Coaster, World 6-6 in New Super Mario Bros. U.
 * Spine Coaster Stowaways, World 6-6 in New Super Luigi U.
 * Bullet Bill Base, World 6-6 in Super Mario 3D World.
 * Cliffside Slide, World 6-6 in Donkey Kong Country: Tropical Freeze.
 * Pyro Guy Peak, World 6-6 in Yoshi's New Island.
 * World 6-6 in Puzzle & Dragons: Super Mario Bros. Edition.
 * Feel Fuzzy, Get Clingy, World 6-6 in Yoshi's Woolly World.