The Inland Empire is a metropolitan area and region inland of and adjacent to coastal Southern California in the Greater Los Angeles area, focusing around the cities in Riverside and San Bernardino county with Los Angeles County and Orange County to the west. The region, at its narrowest definition, includes the cities of northwestern Riverside County and southwestern San Bernardino County that are part of the contiguous urbanized area of Greater Los Angeles. It is sometimes considered to include the desert communities of the Coachella and Victor Valleys, respectively on the other sides of the San Gorgonio Pass and San Bernardino Mountains from the Santa Ana River watershed that creates the majority of the Inland Empire. A much wider definition includes the entireties of Riverside and San Bernardino counties, stretching east to the Nevada and Arizona borders and covering a larger area than West Virginia; this definition is primarily used by the US Census Bureau, which exclusively delineates metropolitan areas at the county level.
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