Alcatraz Island the hands of Confederate sympathizers. Alcatraz, built as a "heavily fortified military site on the West Coast", formed a "triangle of defense" along with Fort Point and Lime Point, and ensured security to the bay. The island was also the site of the first operational lighthouse on the West Coast of the United States. Alcatraz never fired its guns offensively, though during the war it was used to imprison Confederate sympathizers and privateers on the west coast. Because of its isolation from the outside by the cold, strong, hazardous currents of the waters of San Francisco Bay, Alcatraz was used
Alcatraz Wharf and sank in deep water off the wharf in the early 1910s. Her crew of forty-two men escaped by jumping into the bay and swimming ashore. Seismic rehabilitation of the wharf occurred in the early 2000s. The retrofit to the existing wharf and its facilities consisted of concrete demolition, excavation, and installation of tiebacks. Reinforced steel and concrete were added to a new deck. Work was also done on the deteriorated piles under the wharf deck.David Finney is the youngest person to swim the South End Rowing Club Alcatraz Swim when he swam it in 2015 at ten years old.