The term sixth borough is used to describe any of a number of places not geographically co-extensive with any of the five boroughs of New York City, that have instead been referred to as a metaphorical part of the city by virtue of their geographic location, demographic composition, special affiliation with New York City, or cosmopolitan character. The list has included adjacent cities and counties in the New York metropolitan area as well as in other states, U.S. territories, and foreign countries. The list of places referred to as a sixth borough has included locations as diverse as Riker's Island; Philadelphia; Beverly Hills, California; Nashville, Tennessee; and most recently, China.