> <i>Siena, Liverpool, Kyoto, Manhattan are examples of natural cities.</i><p>Nit: Kyoto is actually one of few major cities in Japan (another being Sapporo) that is <i>not</i> "natural", being built on a strict grid pattern as a copy of Chinese former capital Chang'an. However, this planning happened in 794 (not a typo), so it has had a bit of time to evolve since!