For the location, Old Nutura, or Natura before the time change.
Natura is the world that Chaos came from. It is a planet void of almost all its natural resources and animal/plant life. Humans are only able to survive because artificial sustenance and water can be produced in mass quantities. People there are normally corrupt and immoral (but not always). It is a very dangerous place, and only one massive city covers the entire planet.
Chaos and a few others traveled back in time so that the city would never have been built. This created the current Natura.
- The word "natura" means "nature" in Latin, which is a contradiction given the planet's state.