Barrier City

The Barrier Cities is an invention of Dr. Sid in the movie Final Fantasy: The Spirits Within. The Barrier Cities the remaining settlements of the humans on Earth and is the only shelter for them against the Phantoms.

History
Barrier Cities began as military troop facilities which were built seventeen years after the Leonid Meteor which carried the Phantoms fell on Earth. A total of 130 facilities were built across the world as a base operation for the troops of the United States Military Forces (USMF) in their combat against the Phantom threat. However, due to the development of the Zeus Cannon in 2055, some of the Barrier Cities weren't completed until two years later.

During that time, human population began moving into the Barrier Cities, due to the death of plant species which depleted the world's oxygen. Oxygen generators were built within the Barrier Cities, and life outside these settlements became almost impossible.

List
The only known Barrier Cities are:
 * New York Barrier City, which is the base operations of the New York USMF as well as the headquarters of the Council.
 * Houston Barrier City, where the Council evacuated themselves after the Phantom attack on New York Barrier City.
 * San Fransisco Barrier City, which was attacked by Phantoms and where General Hein lost his wife and daughter.