【How-to】How tall is the golden gate bridge

Officially titled “U.S. Penitentiary, Alcatraz”, the institution opened on July 1, 1934 and closed on March 21, 1963. How many cells were there? There are 336 “main line” cells and 42 “solitary confinement” cells in the Cellhouse. The prison was never filled, though, and the average population was about 260 men.