Port Costa School, Historic school building in Port Costa, California, US.

Port Costa School is a two-story building with Classical Revival design, featuring symmetrical elements and large windows that allow natural light to fill the interior spaces. The structure sits on a substantial piece of land near Plaza El Hambre with the Carquinez Strait visible in the distance.

Residents voted a bond in April 1911 and construction began that year; the school opened in 1912. Architect William Wilde, a Danish immigrant, designed the Classical Revival building. It closed in 1966 as the population declined, by then part of the John Swett Unified School District. The building was listed on the National Register of Historic Places on May 25, 1988.

The building is maintained by the Port Costa Conservation Society, which keeps it in use as an event space. Its name comes simply from the town it was built to serve, Port Costa, and it is listed on the National Register of Historic Places. Visitors today encounter the former classrooms reused for gatherings rather than as a school.

The building now operates as an event venue managed by volunteers who organize activities and meetings throughout the year. Visiting is best timed around scheduled community events, which provide opportunities to see the space in use and meet local people.

The building overlooks the Carquinez Strait, a waterway that connected the town to regional shipping routes and made education here relevant to the maritime economy of the area. This water connection shaped how the school and community related to the broader world outside Port Costa.