Library of Congress
Loc: America's Story: First Prisoners Arrived at Alcatraz
Why is Alcatraz Penitentiary called "The Rock?" Who is sent there? This Library of Congress site has more information and photographs.
OceanView Publishing
Alcatraz History: Welcome to Alcatraz History
The entire history of the famous Alcatraz prison known as "The Rock," beginning with 1847, when "The U.S. Army took notice of "The Rock" and its strategic value as a military fortress."
Other
University of Nevada: Alcatraz Occupation: 30 Years Later
This article has many quotes from people that were involved with the Indian Occupation of Alcatraz about what they remember. This site also provides many links to pictures and stores about the takeover.