Labyrinth Zone
Location- South Island
While South Island has a large number of mazes under it, the most complex collection of these has to be the Labyrinth Zone. This collection of partly submerged tunnels cover a wild amount of the under neither of the island as well as having a number of above ground ruins which act as entrances (S1GG). On top of part of the zone, Robotnik built his Scrap Brain Zone so as to make it hard for an enemy, such as Sonic, to enter and stop him.
Games Appearing in-
Sonic 1 (MD, MS, GG), Sonic Drift (GG)
Animals found Here-
Penguin, Walrus
Image from- Sonic 1 (MD)