Alcatraz Island Federal Prison(1933-63) in San Francisco

Alcatraz Island is located in the San Francisco Bay, 1.5 miles (2.4 km) offshore from San Francisco,California,USA .

Alcatraz, the island measures 1,675 feet (511 m) by 590 feet (180 m) and is 135 feet (41 m) at highest point during mean tide. However, the total area of the island is reported to be 22 acres (8.9 ha

Often referred to as "The Rock," the small island was developed with facilities for a lighthouse, a military fortification, a military prison (1868), and a Federal Prison  from 1933 until 1963.

^{Attorney General Robert F Kennedy ordered the penitentiery closed on March 21,1963 because the penitentiary cost much more to operate than other prisons(nearly $10 per prisoner per day,as opposed to $3 per prisoner per day at Atlanta)and half a century of salt water saturation eroded the buildings}

In 1972 Alcatraz became a national recreation area and received designation as a National Historic Landmark  in 1986.

This 1963 image shows the last prisoners depart from Alcatraz Island federal prison in San Francisco. The National Park Service on Thursday celebrated the 50th anniversary of Alcatraz Island's closure as a federal penitentiary with an exhibit of newly discovered photos of the prison's final hours