Commencing in 1797, and lasting through the Spanish and Mexican administrations of Alta California, Fort Mason was one of two sites in San Francisco Bay that was armed with artillery for the defense of the harbor.

For over forty years under the American administration, it played a role in the coastal defenses of the bay from the Civil War to post-Spanish-American War. It also served as an important element in the first submarine mining of San Francisco Bay in the Spanish-American War.

From the Spanish-American War to the Korean War, Fort Mason was the headquarters of the San Francisco Port of Embarkation through which millions of men and millions of tons of supplies were transported into the Pacific. A long list of distinguished generals, commanding the Military Division of the Pacific, live here in Quarters One and Two.

The collection of military structures dating from the 1850's to the Korean War illustrates the evolution of an Army post - and coastal fortifications to a lesser degree - over a period of one hundred years.

The contrasts and many moods of the architecture, the effect of the Army's caste system on the quarters, the charm of the earliest officers' row, the simple lines of the Endicott battery, the WPA architecture of the Great Depression, the Army's determination in landscaping — all these blend together to present a history of this place and its times.