Merit: A Night at Deadvlei. The night before returning to Windhoek, we spent several hours at Deadveli. The moon was bright enough to illuminate the sand dunes in the distance, but the skies were still dark enough to clearly see the milky way and magellanic clouds. Deadveli means “dead marsh. The camelthorn trees are believed to be about 900 years old, but have not decomposed because the environment is so dry. (Photo and caption by Beth McCarley/National Geographic Traveler Photo Contest)

In northwest Russia, in a small village called Alekhovshchina, Nadia Sablin's aunts spend the warmer months together in the family home and live as the family has always lived, chopping wood to heat the house and making their own clothes. Sablin's book of photographs, “Aunties: The Seven Summers of Alevtina and Ludmila”, is published by Duke University Press. Here: “Two-Handed Saw, 2014”. (Photo by Nadia Sablin)

Cave Diver, Anhumas Abyss, Bonito, Brazil: The Anhumas Abyss is an underground cavern with a crystal-clear lake below, more than 260 feet (79 m) deep. A visitor must enter through a narrow opening at the top of the chamber and rappel into the cave. Snorkeling and scuba diving in the lake reveal amazing scenery. Distinctive, conical limestone stalagmites and stalactites occupy the lake and the surrounding area, some reaching 65 feet (20 m) high. (Photo by Marcio Cabral/Nature’s Best Photography Awards 2017)

Jean-François Leroy launched Visa Pour l’Image, the international photojournalism festival, in Perpignan in 1989. Before heading up the festival, Leroy was shooting reportage for the agency Sipa Press and also working for Photo-Reporter, Le Photographe, Photo-Revue and Photo Magazine. He is the chairman of the company Images Evidence. Photo: 2008 Visa d'or Feature: Brent Stirton. Conservation Rangers from an Anti-Poaching unit work with locals to evacuate the bodies of four Mountain Gorrillas killed in mysterious circumstances in the park, July 24, 2007, Virunga National Park, Eastern Congo. (Photo by Brent Stirton/Exclusive by Getty Images)

Visitors watch as Grigory Broverman, a member of the Cryophile winter swimmers club, pours a bucket of cold water over his 6-year-old daughter Liza during a flash mob, part of a celebration of Polar Bear Day at the Royev Ruchey Zoo in a suburb of the Siberian city of Krasnoyarsk, Russia, November 29, 2015. The air temperature was around minus 5 degrees Celsius. (Photo by Ilya Naymushin/Reuters)

Neil Zeller's snaps were taken across Canada, where he photographs the northern lights dancing across a dark night sky. In one stunning shot, Zeller, 42, even manages to capture a flash of lightning beneath a storm cell while an aurora gives off a magnificent green glow. The photographer, from Calgary, Alberta, describes himself as a night person, and became interested in night photography about 10 years ago. (Photo by Neil Zeller/Caters News)

“The Challenge!” Young boy relishes in a game of tug of war before school. Photo location: Lake Titicaca, Peru. (Photo and caption by Paul Heyman/National Geographic Photo Contest)