Sunnyvale (/ˈsʌniveɪl/ or /ˈsʌnivəl/), officially the City of Sunnyvale, is a city located in Santa Clara County, California. As of the 2010 United States Census, the population was 140,095.The city is one of the major cities that make up the Silicon Valley located in the San Francisco Bay Area. It is the seventh most populous city in the San Francisco Bay Area. Sunnyvale is bordered by portions of San Jose to the north, Moffett Federal Airfield to the northwest, Mountain View to the west, Los Altos to the southwest, Cupertino to the south, and Santa Clara to the east. It lies along the historic El Camino Real and Highway 101.