San Diego is a coastal Southern California city located in the southwestern corner of the continental United States. As of 2006, the city has a population of 1,256,951. It is the second largest city in California and the eighth largest city in the United States. It is the county seat of San Diego County. and is the economic center of the San Diego–Carlsbad–San Marcos metropolitan area, the 17th-largest metro area in the U.S. with a population of.9 million as of 2006, and the 21st largest Metropolitan area in the Americas when including Tijuana. San Diego apartments for rent comparison page shows most up to date rent information on San Diego apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.