These frozen caves seem almost otherworldly as they daylight illuminates them. Matej Kriz’s shots reveal the beauty of the brilliant caves, but he’s also very aware of how deadly they can be. The photographer captured the amazing shots in the Vatnajokull National Park on the Breidamerkurjokull glacier tongue. Here: The ice caves, taken in the Vatnajokull National Park in Iceland, on November 11, 2017. (Photo by Matej Kriz/Caters News Agency)

Underwater photographer of the year – winner. Dancing Octopus by Gabriel Barathieu (France). Location: Island of Mayotte, off the coast of south-east Africa. “Balletic and malevolent”, one judge said of this octopus, hunting in a lagoon. Barathieu waited until spring tides when there was just 30cm of water on the flats and plenty of light in the shallows. (Photo by Gabriel Barathieu/UPY2017)

Sophie and Sarah, old English sheepdogs, watch the sea from their plastic chairs. Amateur photographer Cees Bol, from the Netherlands, documents the lives of his beloved pooches Sophie and Sarah by taking pictures of them every day. (Photo by Cees Bol/Caters News Agency/Mercury Press)

Cuban girls dressed as nurses and a lizard wait for their turn to dance during a visit by the Gay Men's Chorus of Washington in Havana July 13, 2015. The choir made its first appearance on July 12, 2015 in Cuba as part of a tour that will include a dozen concerts in the context of the restoration of relations between the island and the United States. (Photo by Enrique de la Osa/Reuters)

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)

For France, the trauma of the Algerian War (1954-1962) was not unlike the experience of the Vietnam War for the United States. But, unlike the conflict in Vietnam, few photographic documents exist from that period in Algeria: it is as if the French responded with collective amnesia. Marc Garanger’s Algerian Women is one of the few photographic essays dedicated to that painful period... Photo: A 1960 photograph of an Algerian woman in a French regroupment village. (Photo by Marc Garanger)

Hermes Cifuentes, who is also known as “Brother Hermes”, performs an exorcism on Marleny Munoz, 55, who claims to be possessed by spirits in La Cumbre, Valle July 7, 2012. Cifuentes says he has performed more than 35,000 exorcism rituals in the past 25 years. (Photo by Jaime Saldarriaga/Reuters)