-
Spanish explorer Lt. Juan Manuel de Ayala maps San Francisco Bay and names an island "de los alcatraces". -
The Alcatraz lighthouse begins service as the first lighthouse on the Pacific Coast. -
Alcatraz is designated as the "Pacific Branch, U.S. Military Prison". -
The new cellhouse (Alcatraz's third prison which still stands today), built with convict labor, is completed and prisoners move in.
-
Alcatraz is transferred to the Federal Bureau of Prisons. 32 of the worst military prisoners remain on the island in civilian custody.