Most Bay Area counties now use vote centers, but Solano County doesn't. KCRA reports that Solano and San Joaquin counties haven't adopted the system, so voters there vote by mail or at their assigned polling place on Election Day.
Drop-off sites: ballot drop-off locations inside public buildings, such as city clerks' offices and libraries in Benicia, Dixon, Fairfield, Rio Vista and Suisun City, among others,, are open Oct. 5–Nov. 3 during posted hours. The Registrar of Voters at 675 Texas St., Suite 2600, Fairfield, is open 8 a.m.–5 p.m. on Saturday, Oct. 31, and 7 a.m.–8 p.m. on Election Day. There's also a 24-hour drop box on Union Avenue.
Polling places: use the county's polling place lookup, which also shows your sample ballot. Each site's hours and holiday closures are listed on the county's drop-off page.