Dr. Robotnik’s giant flying station, which is also the launching platform for a rocket to fly into space, the Wing Fortress Zone is one of the most intimidating weapons Robotnik has ever used to take over the West Side Island. Even Sonic couldn’t stop the flying fortress – luckily, however, Tails was also on his side, modifying the Tornado plane to bring the supersonic hero aboard the Wing Fortress Zone.

The airspace above Sonic’s world, the Sky Chase Zone is not quite a place, but rather a description of the situation. The Sky Chase Zone can be anywhere in the airspace, but is the area immediately around Dr. Robotnik’s giant mobile flying base. Blue skies, a white sheet of clouds, and hundreds of hostile robots are what will greet the heroes here as they seek to chase the villain in the Tornado plane. It was on the Sky Chase Zone that players could see the Tornado in action for the first time.

The legendary base of Dr. Robotnik and one of the most dangerous places Sonic has visited. Located somewhere on the West Side Island, the Metropolis Zone is a huge mechanized city. From game to game this city changes its appearance. Initially similar to an ordinary but very heavily protected factory, the city later became much more like a huge megapolis with giant buildings reaching into the sky and roads twisting in bends that could make one dizzy.

Located somewhere on the West Side Island, the Oil Ocean Zone is a fuel plant operating on such a large scale that entire fuel seas have formed around it. The air here is contaminated, and to move around the plant, its mechanical workers use special submarines capable of navigating fuel seas.