"Erbil Citadel Town, which is situated dramatically on top of an artificial, 32-meters high earthen mound, and visually dominating the expansive modern city of Erbil, is believed to have been in continuous existence for 7000 years or even more. Thus, it may be regarded as the oldest continuously inhabited settlement in the world. Because of its past fortifications and steeply inclined mound, which is at some locations nearly 45 degrees, it has managed to survive numerous sieges and fierce attacks. The existing fabric, however, goes back to several hundred years but is, nevertheless, of extreme vernacular architectural and urban interest, not only for Iraq but also for humanity at large."
http://whc.unesco.org/en/tentativelists/5479/
