Glitch City

To perform this glitch, enter the Safari Zone. Enter the Safari Zone building again, and when asked if you are leaving early, say no. Then save the game and reset. Try to exit the Safari Zone. You should be asked if you want to enter. Say no and once you're out of the building, walk or Fly somewhere else. After 500 steps, you will be transported to the Safari Zone building. Exit the building, and you'll be in Glitch City! Be aware that most cities and inside buildings don't work. You can also use this as a walk through walls glitch by having your 500th step be jumping on a ledge and while inside the Safari Zone building, having all your Pokemon faint, preferably by poisoning your last Pokemon before performing the glitch. This way, you will go to the Pokemon Center, not Glitch City, and you will be able to walk through walls, because the game thinks you are still jumping and in the air.