Walnut Creek is a city in Contra Costa County, California, United States, located 16 miles (26 km) east of the city of Oakland in the East Bay region of the San Francisco Bay Area. Although not as large as neighboring Concord, Walnut Creek serves as a hub for the neighboring cities within central Contra Costa County, due in part to its location at the junction of the highways from Sacramento and San Jose (I-680) and San Francisco/Oakland (SR-24), as well as its accessibility by BART.