Place

Building a New Prison: Prisoners at Work

Black and white photograph of men working on the construction of the new prison.
Construction of the new prison between 1909-1910

National Archives

In the early 1900s, the population of men incarcerated at Fort Alcatraz grew to more than 500. Most were soldiers who committed crimes while fighting Filipino nationalists after U.S. annexation of the Philippines following the Spanish American War (1898). In 1907, as the prison population grew, the army renamed the island from Fort Alcatraz to U.S. Military Prison Alcatraz Island. Incarcerated soldiers were forced to tear down the Civil War brick buildings and cannon batteries and construct what you see here today, including this Powerhouse built in 1910 to power a new prison.

In 1912, when that new 600-cell prison opened atop the island, it was the largest steel-reinforced concrete building in the world. Along with incarcerated soldiers, the new prison held First World War conscientious objectors like Philip Grosser, an anarchist who refused to work and was shackled in an unlit cell below the prison for weeks at a time.

How would you stand up for what you believe in?

Alcatraz Island , Golden Gate National Recreation Area

Last updated: March 2, 2021