The famous island federal prison in San Francisco Bay, retired and now a national park site.
Built on the site of an earlier military fortification and prison, Alcatraz held some of the country’s most notorious inmates before closing in the 1960s. Park rangers and visitors report cold spots in the cellblocks, particularly in solitary confinement Cell 14D, along with clanging and distant voices.
Cold spots in the cellblocks, sounds from solitary, and a presence in 14D.