Fifty years ago, the notorious Alcatraz prison shut its gate behind guard Jim Albright as he escorted the last inmate off the island on March 21, 1963.

This 80,000-acre urban park is one of the nation's largest and the most beautiful. Spanning 70 miles, it's rich in history, plant life and wildlife. It's also a major feat of rehabilitation and restoration.

Alcatraz Island, home to its namesake famous prison off the San Francisco Bay, welcomed back its last inmates for the 50th anniversary of the closure of one of the most notorious penitentiaries in the world.

The National Park Service marked the 50th anniversary of the closure of the Alcatraz federal penitentiary on Thursday with an exhibit of recently discovered photographs of the prison's final day on March 21, 1963.

Tours of the Golden Gate Bridge inaugurated during its 75th anniversary in 2012 are back for a second season starting April 1, 2013.