A spectator reacts after a Brazil Volleyball win during Paris 2024 Olympics in Women's Preliminary Round, Pool B Brazil vs Poland at South Paris Arena 1 in Paris, France on August 04, 2024. (Photo by Siphiwe Sibeko/Reuters)

Filipinos wade through floodwaters along a road in Manila, Philippines, 22 August 2025. The National Disaster Risk Reduction and Management Council (NDRRMC) on 22 August raised its alert level and warned residents of flooding in low-lying areas and landslides in mountainous communities brought by a storm. The government weather bureau said a Tropical Cyclone Wind Signal Number 01 is raised over 17 areas due to Tropical Depression “Isang”, which made landfall over the Aurora province. (Photo by Francis R. Malasig/EPA)

A Russian ground staff member signals to the pilot of a Sukhoi Su-25 fighter jet at the Hmeymim air base near Latakia, Syria, in this handout photograph released by Russia's Defence Ministry October 22, 2015. (Photo by Reuters/Ministry of Defence of the Russian Federation)

France's Alexia Richard looks up after falling in. loss to Spain in a beach volleyball match at the 2024 Summer Olympics, Wednesday, July 31, 2024, in Paris, France. (Photo by Robert F. Bukaty/AP Photo)

Switzerland's Zoe Verge-Depre, right, sets up a shot for Esmee Boebner in a beach volleyball match against Canada at the 2024 Summer Olympics, Wednesday, July 31, 2024, in Paris, France. (Photo by Robert F. Bukat/AP Photoy)

A member of the German wireless police picks up signals on the radio equipment he carries on his back, while his colleague takes notes. (Photo by General Photographic Agency/Getty Images). Circa 1925

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.

People wear masks to help guard against the Coronavirus in downtown Tehran, Iran, Sunday, February 23, 2020. On Sunday Iran's health ministry raised the death toll from the new virus to 8 people in the country, amid concerns that clusters there, as well as in Italy and South Korea, could signal a serious new stage in its global spread. (Photo by Ebrahim Noroozi/AP Photo)