The Isolated American Island Prison

McNeil Island once housed a high-security prison that was accessible only by boat. Because the island had no bridge to the mainland, inmates were completely cut off from the outside world.

This unique facility operated for over a century, relying entirely on ferry transport for staff, supplies, and visitors. The remote location turned the surrounding cold waters of Puget Sound into a natural, inescapable barrier. It remained one of the few island prisons in the United States, creating an eerie sense of seclusion. Today, the island is largely uninhabited and returned to nature.