The Haʻikū Stairs, also known as the Stairway to Heaven or Haʻikū Ladder, is a steep hiking trail on the island of Oʻahu. The trail began as a wooden ladder spiked to the cliff on the south side of the Haʻikū Valley. It was installed in 1942 to enable antenna cables to be strung from one side of the cliffs above Haʻikū Valley to the other. A building to provide a continuous communication link between Wahiawā and Haʻikū Valley Naval Radio Station was constructed at the peak of Puʻukeahiakahoe, elevation about 2,800 feet (850 m). The antennae transmitted very low frequency radio signals from a 200,000-watt Alexanderson alternator in the center of Haʻikū valley. The signals could reach US Navy submarines as far away as Tokyo Bay while the submarines were submerged.

Hemispheric color differences on Saturn's moon Rhea are apparent in this false-color view from NASA's Cassini spacecraft in this March 2, 2010 file photo. (Photo by Reuters/NASA/JPL/SSI)

A woman wearing a face mask and a child sit between rail tracks, during the imposition of large-scale social restrictions by the government to prevent the spread of the coronavirus disease (COVID-19) in Jakarta, Indonesia, April 12, 2020. (Photo by Willy Kurniawan/Reuters)

Shoppers walk past crocodiles for sale at a market in Bata on February 3, 2015. Markets in Equatorial Guinea sell a variety of animals including pangolins, monkeys and crocodiles as food. (Photo by Carl De Souza/AFP Photo)

General view of the atmosphere at the Halloween celebrating in city centre on October 29, 2021 in Newcastle, United Kingdom. (Photo by Newcastle New Projects)

Cheetah Darcy enjoys her newly-developed Cheetah Territory that covers 10,000 square at Yorkshire Wildlife Park, near Doncaster, UK on Wednesday, August 16, 2023. Darcy, who is four-years-old, travelled from Ireland's Fota Wildlife Park to YWP last week where she will be joined by 13-year-old male Brooke who is on his way from the Bristol Zoo Project as a recommendation by the European Endangered Species Programme. (Photo by Danny Lawson/PA Images via Getty Images)

Capturing this picture of lightning striking near Blackpool Tower has earned Stephen Cheatley the UK Weather Photographer of the Year award 2018. (Photo by Stephen Cheatley/Bav Media)

Undated handout photo issued by Guinness World Records of Fabio Reggiani from Italy who has made it into the Guinness Book of World Records for constructing the worlds largest rideable motorcycle measuring 5.10 meters (16ft 8.78 in) from the ground to the top of the handlebars. Six times larger than a normal motorcycle, it's 10.03 m long, 2.5 m wide, and weighs approximately 5,000 kg (5 tonnes). (Photo by Guinness World Records/PA Wire)