Stairway to Heaven: Island of Oahu, Hawaii.

The Haiku Stairs, or the Stairway to Heaven, is a semi-secret forbidden hike on the island of Oahu, Hawaii. The stairs were originally built in 1943 to install antenna cables as part of a larger military radio communication system to communicate with US Navy submarines as far away as Tokyo Bay. The original wooden steps were replaced by metal, cable-supported stairs in the early 1950s when the US Coast Guard took over the installation. Soon after, the military decommissioned the entire site and it was opened to the public–until 1987.