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.

Base jumper Denis Odintsov from Russian leaps from the 300-meters Open Deck of the Malaysia's landmark Kuala Lumpur Tower during the International Tower Jump in Kuala Lumpur on September 27, 2013. Some 103 professional base jumpers from 20 countries are taking part in the annual event. (Photo by Mohd Rasfan/AFP Photo)

These photographs are the work of urban explorer Dr Bradley Garrett who made headlines back in 2012 when he posted a series of snaps from the top of The Shard skyscraper while it was still under construction. Garrett, now a researcher at the University of Oxford, took these shots during his time with the London Consolidation Crew (LCC), a loose collection of urban explorers based in the English capital. Photo: Bradley Garrett stands on the edge of the Ritz-Carlton Chicago as lightning strikes in the distance in Chicago, US. (Photo by Bradley L. Garrett/Barcroft Media)

The overall winner of the 2013 Red Bull Illume photography competition from Lorenz Holder. (Photo by Lorenz Holder/Red Bull)

In this photo provided by Skydive Chicago, escape artist Anthony Martin falls while handcuffed and locked inside a box after being dropped from an airplane over Ottawa, Ill., Tuesday, August 6, 2013. (Photo by Joe Silva/AP Photo/Courtesy of Skydive Chicago)

The Hawksbill Crag, also known as Whitaker Point, is located along the northern edge of the Upper Buffalo Wilderness in the Ozark National Forest, just south of the Buffalo National River. It is easily one of the most photograped and recognizable features in Arkansas, and is often seen on publications depicting the outdoors in Arkansas. The hike to it is an easy 3.0 mile round trip, and offers scenic vistas, huge boulders, beautiful waterfalls and colorful wildflowers.

The holder of half a dozen world records will walk across the Grand Canyon on a steel cable with nothing but the Little Colorado River 1,500 feet below on June 23. With no tethers or safety nets, the walk will be the highest tightrope attempt ever for the 34-year-old, at a height taller than the Empire State Building. Last year, Wallenda, a seventh-generation member of the “Flying Wallendas” family of acrobats, became the only person to walk a wire over the brink of Niagara Falls. Photo: Nik Wallenda walks across a tightrope 200 feet above U.S. 41 on January 29, 2013 in Sarasota, Florida. (Photo by Tim Boyles)

Mt.Huanshan, or Mount Hua is one of the five sacred mountains in China. The other four are Taishan in Shandong, Songshan in Henan, Hengshan in Shanxi and Hengshan in Hunan.
Mt. Huashan is reputed as the most precipitous of the five.