Alcatraz Island

Alcatraz, also known as "The Rock" is an island that is located 1.5 miles from San Francisco, Califormia.

History
Originally tasked as a lighthouse, Alcatraz is far more known for its role as a prison than anything else. Starting in 1861, the island was used as a military prison, long believed to be unescapable because of the treacherous waters of the San Francisco Bay that surround it. It wasn't until 1868 that Alcatraz became an officially designated detention facility.