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.

In this August 17, 2016, photo, from left to right, Chhering Chodom, 60, Tashi Yangzom, 50, Lobsang Chhering, 27, and Dorje Tandup, 58, drink milk tea on the side of the road. For centuries, the sleepy valley nestled in the Indian Himalayas remained a hidden Buddhist enclave forbidden to outsiders. Enduring the harsh year-round conditions of the high mountain desert, the people of Spiti Valley lived by a simple communal code – share the Earth's bounty, be hospitable to neighbors, and eschew greed and temptation at all turns. That's all starting to change, for better or worse. (Photo by Thomas Cytrynowicz/AP Photo)

Two Inuit children at Point Barrow, Alaska, holding the tusks of a large walrus, probably killed for food, circa 1930. (Photo by General Photographic Agency/Getty Images)

Two young boys kneel on stools on either side of a round table as one uses a match to this the other's cigarette, November 12, 1928. (Photo by FPG/Getty Images)

“We take rusty old junk and we put love into it”. The old Motor City has a unique style in bicycles these days: from fat wheels and fake fuel tanks to stretched cycles with powerful sound systems – and even a family-sized BBQ. “Detroit’s custom bike scene developed alongside Slow Roll, a weekly cycle ride started in 2010 by Jason Hall and Mike MacKool. Now upwards of 2,000 people turn up each Monday to cruise a different part of the city. The week I go the crowd seems evenly split between black and white, male and female, city and suburbs. It’s the most inclusive cycle event I’ve ever witnessed”. (Photo by Jason Walker/Slow Roll Monday Nights)

Polar frame, by Dmitry Kokh, Russia. When Kokh’s boat approached the small island of Kolyuchin in the Russian High Arctic, which had been abandoned by humans since 1992, he was surprised to spot movement in one of the houses. Binoculars revealed polar bears – more than 20 in total – exploring the ghost town. Dmitry used a low-noise drone to document them. (Photo by Dmitry Kokh/Wildlife Photographer of the Year 2022)

A man walks on a bridge crossing over the Besor stream on a rainy day, near Kibbutz Tze'elim in Israel's southern Negev desert February 16, 2017. (Photo by Amir Cohen/Reuters)

Fireworks are seen during New Year's celebrations in Tirana, Albania, on December 31, 2024. (Photo by Florion Goga/Reuters)