Alcatraz Citadel island and replaced the lower prison, with a capacity of 307 inmates. Alcatraz was renamed as the "Pacific Branch, U.S. Military Prison” in 1907, and as the importance of the Island citadel became less and less obvious due to modernization of the naval facilities, infantry soldiers were shifted and prison guards brought in their place. It developed a reputation for its brutal methods of torturing prisoners, placing prisoners in pitch black cells for up two weeks. Alcatraz was barely affected by the 1906 San Francisco earthquake which devastated the city, and the prison population dramatically increased as prisoners were temporarily
Escape from Alcatraz (triathlon) foot race, but by making it an out-and-back run rather than a one-way course, became known as a "Double Dipsea". The course has remained the same over the years and celebrated its 35th anniversary in 2015. Participants are limited to members of the Dolphin Club and The South End Club. The Dolphin Club is the host and sponsor of the event. The annual public Escape from Alcatraz triathlon, organized by IMG, now takes place in early June. The current course consists of a swim starting near Alcatraz Island, a run from the bay to the transition zone at Marina Green,