San Diego County has a population of more than 3 million people, of which, nearly half live in the city of San Diego itself. Other cities in the county include Chula Vista, Oceanside, Carlsbad, San Marcos, Escondido, Poway, Encinitas, and Vista. The county is home to many people who have moved to San Diego from elsewhere.
Located in the very southwest corner of California, San Diego borders Orange and Riverside Counties to the North, Imperial County to the East, Baja California, Mexico to the South, and the Pacific Ocean to the West. San Diego County has over 70 miles of Pacific Ocean coastline. San Diego has a mediterranean climate that borders on semi-arid. The Pacific Ocean has a moderating effect on temperatures near the coast, which keeps temperature variances much less than those of areas further inland.