Discovery Bay is in the eastern Contra Costa County, California about 60 miles (97 km) from San Francisco.
In July 2007, Discovery Bay received its own ZIP code: 94505. Formerly it had shared 94514 with Byron. The ensuing celebration included a world record-setting paddle boat raft-up.
Discovery Bay has a short history. It was begun as a planned community in 1964, and originally designated as "Riverside" and "River Lake." It was built on land known as the Byron Tract, which was previously used for growing barley and potatoes.