Tupolev Tu-142MK, a Soviet and Russian maritime reconnaissance and anti-submarine warfare aircraft flies above a statue of Soviet Union founder Vladimir Lenin during a rehearsal of the Naval parade in St.Petersburg, Russia, Thursday, July 28, 2022. The celebration of Navy Day in Russia is traditionally marked on the last Sunday of July and will be celebrated on July 31 this year. (Photo by Dmitri Lovetsky/AP Photo)

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 sailor of the Marshal Shaposhnikov anti-submarine destroyer takes part in the “Vostok-2022” military exercises at the Peter the Great Gulf of the Sea of Japan outside the city of Vladivostok on September 5, 2022. The Vostok 2022 military exercises, involving several Kremlin-friendly countries including China, takes place from September 1-7 across several training grounds in Russia's Far East and in the waters off it. Over 50,000 soldiers and more than 5,000 units of military equipment, including 140 aircraft and 60 ships, are involved in the drills. (Photo by Kirill Kudryavtsev/AFP Photo)

Actress Hiba Abouk attends Hugo Boss night party 2011 on December 13, 2011 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

A model showcases lingerie during a lingerie show on International Women's Day at a shopping mall on March 8, 2011 in Qingdao, Shandong Province of China. The official theme of International Women's Day 2011 is “Equal access to education, training and science and technology: Pathway to decent work for women”. (Photo by ChinaFotoPress/Getty Images). QINGDAO, CHINA – MARCH 08 2011

In this handout image provided by Perth 2011, HMB Endeavour, the replica of Captain James Cook's ship, is farewelled from Sydney Harbour accompanied by three Olympic class Laser yachts on April 16, 2011 in Sydney, Australia. The ship was farewelled from Sydney to start her circumnavigation of Australia, ending up in Freemantle where she will play a role in the Perth 2011 ISAF Sailing World Championships in December. (Photo by Richard Palfreyman/Perth 2011 via Getty Images)

A worker spreads paddy crop for drying in a rice mill complex on the outskirts of Ahmedabad February 3, 2011. (Photo by Amit Dave/Reuters)

A woman carrying a basket of papayas while walking through a vegetable market in Bangkok, Thailand November 11, 2011. (Photo by Kerek Wongsa/Reuters)