Xi'an
Xi'an was called Chang'an in ancient times. In Classical Chinese it literally means "Perpetual Peace". But from 9 AD-23 AD, during the Xin Dynasty, it was renamed "Constant Peace" (it is said the same way). By the time of the Ming Dynasty it had been named Xi'an (which means "Western Peace"). It was named Xi'an because was in the western part of the Ming Empire.