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.

A general view of the Drax Power Station, illuminated in the colours of the Ukrainian flag, in North Yorkshire, Britain on April 1, 2022. (Photo by Lee Smith/Reuters)

An enthusiast dressed as a zombie takes part in the annual Zombie Walk festival in Prague June 1, 2013. (Photo by David W. Cerny/Reuters)

A woman sells vegetables near a Metro train station in downtown Lima, Peru December 1, 2015. (Photo by Mariana Bazo/Reuters)

Revellers celebrate New Year's Day in central Moscow, Russia, January 1, 2016. (Photo by Tatyana Makeyeva/Reuters)

Internally displaced Syrian children play inside a refugee camp in the Hama countryside, Syria January 1, 2016. (Photo by Ammar Abdullah/Reuters)

Participants take part in a New Year's Jump into the Sea in Portoroz , Slovenia, January 1, 2016. (Photo by Srdjan Zivulovic/Reuters)

Jakub Przygonski at the stage 1 of Dakar Rally, Pisco, Peru on January 7, 2019. (Photo by Kin Marcin/Red Bull Content Pool)