Alcatraz Island at Golden Gate National Recreation Area

Warden's House. After 1907, reinforced concrete became the standard construction material on Alcatraz. Reinforced concrete was not in common use until after the 1906 San Francisco earthquake and fire, when it was quickly and widely adopted throughout California as a construction material (as a result of its superior performance during that event). The new prison building matched other buildings then under construction or just completed at Fort Mason and the Presidio; they were stripped down, or utilitarian versions of the Spanish Colonial, or Mission Revival style.