The Forbidden Cities are what the Elves call human territory. All of the human world we know is part of the Forbidden Cities. Like the name inclines, elves may not enter the Forbidden Cities unless they have permission from The Council. Even with permission, they must have a blue leaping crystal.
Forbidden Cities Visited in the Keeper of the Lost Cities series
San Diego, California
Hollywood, Los Angeles, California
California's White Mountains
- Visited by Sophie, Fitz, Biana, Keefe, Dex, Della, the Collective, Calla, and a number of other gnomes.
-Visited by anyone who has gone to the Sanctuary.
-Visited by Sophie, Fitz, Keefe, Dex, Biana, Della, Mr. Forkle, possibly other members of the Black Swan, and at least one Pyrokinetic in the Neverseen, including Brant or Fintan. Most likely Brant, as Fintan usually stays where it's safe.
London, England- Visited by Sophie, Keefe, Fitz and probably others.