Pokemon: Shadow and Ash
Moonstone city is an isolated city state in what was once the Northwestern Kanto region. The metropolis was constructed within the caldera of Mount moon over 900 years ago during the epic struggle of the Mewtwo wars. It lies only a few dozen miles from the edge of the Red Zone today, and up until about 300 years ago the city was located within the Red zone. Only after the radiation was a sufficient distance away did the Hermetically sealed doors open into a vastly different world.
Moonstone city is known for it's preservation of both advanced technology and technical knowledge. Were it not for the Pewterlords impressive military forces and the cities heavily fortified location it would likely be flying the flag of the Jotorre Empire or that of one of the Salamance Lords of the southern Isles today. The city state is technically a monarchy with the reigning Pewterlord answerable only to the high council that they themselves appoint.