Discovery Bay is a census-designated place in eastern Contra Costa County, California, set within the Sacramento–San Joaquin River Delta about 60 miles from San Francisco. Unlike most East Bay communities, it was engineered rather than organically settled: beginning in the early 1970s, developers converted flat farmland into a deep-water marina community, digging a system of man-made channels and bays so that homes could have private docks and direct access to the Delta's navigable waterways. What began as a weekend and summer resort community has grown into a year-round town of roughly 15,000 residents. Water remains the organizing principle of the place. Many homes sit on canals or bays with private docks and boat slips, and the Discovery Bay Marina anchors a waterfront lifestyle built around boating, fishing, and water sports. Interior streets offer conventional single-family homes for those who value the setting without needing direct water frontage. The community's schools reflect its position at the edge of several East County districts. Students are served by the Byron Union School District for elementary and middle grades, with middle schoolers attending Excelsior Middle School in nearby Byron, and by the Liberty Union High School District for high school, zoned to Liberty High School in Brentwood. Transportation is car-centered. Discovery Bay has no rail station of its own; Highway 4 through Brentwood is the main route out, and the Antioch BART station is about 19 miles away, making the community best suited to East County commuters, hybrid workers, and remote workers. Nearby Brentwood, Oakley, Byron, and Knightsen provide additional shopping, services, and community resources, while surrounding farmland preserves the open, semi-rural feel that drew the community's first residents decades ago.