Fort Mason Fort Mason , once known as San Francisco Port of Embarkation , US Army , in San Francisco , California , is a former United States Army post located in the northern Marina District , alongside San Francisco Bay . Fort Mason served as an Army post for more than 100 years , initially as a coastal defense site and subsequently as a military port facility . During World War II , it was the principal port for the Pacific campaign . Today it is part of the Golden Gate National Recreation Area and the site of several cultural facilities . It is a National Historic Landmark District with over 49 buildings of historic significance , spread over . Geography . Fort Mason can be split into two distinct areas . The upper area , sometimes called Fort Mason , is situated on a headland and was the site of the original coastal fortifications . The lower area , Fort Mason Center , is situated close to water level to the west of Upper Fort Mason , and is the site of the former military port , with its piers and warehouses . The Marina Green lies to the west of Fort Mason , while Aquatic Park is to the east . History . The Civil War prompted the construction of a set of coastal defense batteries located inside the Golden Gate . Initially these defenses were built as temporary wartime structures rather than permanent fortifications and one of these was constructed in 1864 at Point San Jose , as the location of Upper Fort Mason was then known . A breast - high wall of brick and mounts for six Rodman cannons and six 42 - pounder guns were built on the site . Excavation in the early 1980s uncovered the well - preserved remains of the western - half of the temporary battery , and it has now been restored to its condition during the Civil War . The fort was named Fort Mason in 1882 , after Richard Barnes Mason , a former military governor of California . President Grover Cleveland established the Endicott Board in 1885 for the purpose of modernizing the nation ' s coastal fortifications . Chaired by Secretary of War William Endicott , the board recommended new defenses at 22 U . S . seaports , deeming San Francisco Harbor second only to that of New York in strategic importance . As a result , an extensive series of forts , batteries , and guns were built on the harbor , including Fort Mason . The piers and sheds of Lower Fort Mason were originally built from 1912 to warehouse army supplies and provide docking space for army transport ships . By this time , the US Army began to build new bases in Hawaii , the Philippines , and various other Pacific islands . Most of the material for those bases was shipped through San Francisco . By 1915 , the three piers together with their associated warehouse had been completed , and a railroad tunnel driven under Upper Fort Mason to connect with the railroad network along the Embarcadero . With these new facilities , Fort Mason was transformed from a harbor defense post into a logistical and transport hub for American military operations in the Pacific . The Army ferry " General Coxe " provided scheduled transportation from Fort Mason to the processing center at Fort McDowell on Angel Island up to eight times per day during the war . During World War II , Fort Mason became the headquarters of the " San Francisco Port of Embarkation " , controlling a network of shipping facilities that spread across the Bay Area . Over the years of the war , 1 , 647 , 174 passengers and 23 , 589 , 472 measured tons moved from the port into the Pacific . This total represents two - thirds of all troops sent into the Pacific and more than one - half of all Army cargo moved through West Coast ports . The highest passenger count was logged in August 1945 when 93 , 986 outbound passengers were loaded . The Korean War in the 1950s also kept the post busy , and in 1955 the " San Francisco Port of Embarkation " was renamed the " U . S . Army Transportation Terminal Command Pacific " . The embarkation operations continued through the early sixties . In 1965 the headquarters of the US Army Transportation Terminal Command were transferred to the Oakland Army Terminal , and most of Fort Mason ' s embarkation facilities fell into disuse . The Army continues to use and maintain the old officer housing . The National Park Service took over the administration of the site in the 1970s as a part of the Golden Gate National Recreation Area . In 1976 lower Fort Mason became the Fort Mason Center , a non profit organization that provides a destination for programs , events and organizations that support and reflect the evolving cultural fabric of San Francisco and the Bay Area . ( GGNRA ) . Current uses . Some of the old officer housing remains in use by the Army , while some is rented to the public . One of the larger buildings has been converted into a youth hostel , operated by Hostelling International USA . As a whole , the former post is now a mix of parks and gardens and late nineteenth and early twentieth century buildings that are still in use . A path follows the harbor edge , rising along the headland and offering views north past Alcatraz and west to the Golden Gate Bridge . A portion of the site , known as the Fort Mason Center , houses the San Francisco Museum of Modern Art Artists Gallery , Blue Bear School of Music , City College of San Francisco Art Campus , Long Now Museum and Gallery , Greens restaurant , Readers Bookstore , Magic Theatre , the Mexican Museum , Off the Grid , BATS Improv , San Francisco Children ' s Art Center , Museo ItaloAmericano , and California Lawyers for the Arts . The Outdoor Exploratorium is located on the Fort Mason Center campus as well as along the northern path on Upper Fort Mason . The National Park Service headquarters for both the Golden Gate National Recreation Area and the San Francisco Maritime National Historical Park are located in Fort Mason . Operations for the United States Park Police are located in the fort , providing police services for the Golden Gate National Recreation Area in San Francisco and Marin County . Future developments . A proposal exists to extend the F Market & Wharves historic streetcar line to a terminal at Lower Fort Mason . This extension would run from the vicinity of the existing terminal near Fisherman ' s Wharf , westward alongside the San Francisco Maritime Museum and Aquatic Park , and then through the existing , now unused , San Francisco Belt Railroad tunnel under Upper Fort Mason . A technical feasibility study , under the aegis of the National Park Service and San Francisco Municipal Railway , was completed in December 2004 . An Environmental Impact Statement for the extension , involving the San Francisco Municipal Railway , National Park Service and Federal Transit Administration , commenced in May 2006 . The Draft Environmental Impact Statement ( DEIS ) was completed in March 2011 , and was scheduled to be reviewed by December 2011 .