The Inland Empire is a metropolitan area and region located inland from coastal Southern California. Centering on the cities of Riverside and San Bernardino and encompassing their respective counties, it lies to the east of Los Angeles County and Orange County. The region, in its narrowest definition, includes the cities of northwestern Riverside County and southwestern San Bernardino County that are part of the urbanized area of Greater Los Angeles. It is sometimes considered to include the desert communities of the Coachella and Victor valleys opposite the San Gorgonio Pass and San Bernardino Mountains from the Santa Ana River watershed, which creates the majority of the Inland Empire. The region's most comprehensive definition includes all of Riverside and San Bernardino counties, stretching east to the borders of Nevada and Arizona and covering a larger area than West Virginia. This is the definition primarily used by the U.S. Census Bureau and the Office of Management and Budget (OMB), the two federal agencies that exclusively delineate U.S. metropolitan areas at the county level.
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