Riverside County is one of 58 counties in the U.S. state of California. The name was taken from the city of Riverside, which is the county seat.
Riverside County is included in the Riverside-San Bernardino-Ontario, CA Metropolitan Statistical Area, also known as the Inland Empire. The county is also included in the Los Angeles-Long Beach, CA Combined Statistical Area. There is a high concentration of sprawling house tract communities around Riverside and along the Interstate 10, 15, and 215 freeways.