North Island is the setting of Sonic the Hedgehog 4. It contains four different zones on the left and the three more on the right for the game. The island was a relatively peaceful place.
- Splash Hill Zone: A Green Hill-esque zone, bright and colorful, featuring many springs, speed boosters, and zip-lines.
- Casino Street Zone: A level styled like Casino Night Zone. The level features traditional casino objects, such as bumpers, slot machines, and playing cards.
- Lost Labyrinth Zone: Based off of Labyrinth Zone, this level takes place in dark caves, which includes various traps, underwater sections, and a mine cart ride.
- Sylvania Castle Zone: An ancient ruin of castles, partially flooded.
- White Park Zone: A snow-covered land mixed with a carnival.
- Oil Desert Zone: Based off of Oil Ocean Zone, Oil desert is a ruined oil facility created by Doctor Eggman.
- Mad Gear Zone: Doctor Eggman's headquarters, Mad Gear is very much life Metropolis Zone, which includes various moving gears (hence, the name).
- Sky Fortress Zone: Very similar to the original Wing Fortress Zone, Eggman's vessel flies high in the sky, reaching the ninth and final stages
- E.G.G. Station Zone: The final zone of the game, the E.G.G Station takes place in outer space, very similar to the Death Egg Zone. This level features a series of bosses, and then, the final boss, Eggman's Giant Robot.
- Death Egg Mk.II: Yet another rebuild of the original Death Egg Zone, where Eggman awaits Sonic and Tails.