Concord (/ˈkɒŋkərd/ kon-kərd; formerly Todos Santos) is the largest city in Contra Costa County, California, in the United States. At the 2010 census, the city had a population of 122,067. Founded in 1869 as the community of Todos Santos by Salvio Pacheco, the name was changed to Concord within months. The city is a major regional suburban East Bay center within the San Francisco Bay Area, and is 31 miles (50 km) east of San Francisco.The focal point of downtown Concord is Todos Santos Plaza, which encompasses an entire city block and is known for its farmers market, free summer concerts, and large number of surrounding restaurants. Much of the area immediately around downtown has recently been redeveloped, with new high-density apartment and condominium projects to take advantage of the proximity to public transportation and the vibrant area surrounding the park. Despite this, some crime and homelessness remain issues in the downtown area.
To the north and east of downtown is the older residential area of Concord, with many homes dating back to before World War II. In the far northern edge of town is a primarily industrial area, dominated by the Tesoro Golden Eagle Refinery (which is actually not located within city limits). The southeastern area of the city, centered along Clayton Road, is primarily residential and was mostly developed in the 1960s and 1970s. In the southwest area of the city is the primarily Latino neighborhood known as Four Corners, centered around the intersection of Monument Boulevard and Oak Grove Road.
Until 1995 the city was the eastern terminus of the Concord line of Bay Area Rapid Transit (BART) commuter train system; the line has since been extended eastward to Pittsburg/Bay Point. The County Connection provides limited public transportation in the city and to other points in the county. Buses run from the North Concord BART station to Martinez, the county seat.
Main thoroughfares include Willow Pass Road, Concord Avenue, Concord Boulevard, Clayton Road, Monument Boulevard, Ygnacio Valley Road, Oak Grove Road and Treat Boulevard. The city is also served by Interstate 680, and state highways 4 and 242.
Buchanan Field Airport is a public county-owned airfield in the City of Concord. It currently does not have any scheduled passenger service, but was once served by WestAir, Pacific Southwest Airlines, and later U.S. Airways for a short time.