ISS013-E-17394 (10 May 2006) --- The central Phoenix Metro Area, Arizona is featured in this image photographed by an Expedition 13 crewmember on the International Space Station. The Phoenix, Arizona metropolitan area is the largest in the southwestern United States, and is comprised of 21 contiguous incorporated municipalities. Such a collection of discrete political entities forming a larger integrated urban landscape is referred to as a conurbation by urban geographers. This portion of a high resolution (approximately 9 meters/pixel) photograph (upper image) of the central metro region includes the boundary area between three of the municipalities included in the conurbation: the Cities of Phoenix (upper image, left), Tempe (upper image, center and lower right), and Scottsdale (upper image, upper right).