Descending into the Marum Volcano in Vanuatu, Intrepid explorers found an unusual way of staying warm this winter by spending Christmas day on an active volcano. British climber Chris Horsley, 22, and his friends Gareth Hawken, 30, Geoff Mackley, 50, and Bradley Ambrose, 36, from Auckland, New Zealand, hiked up the Marum Volcano, Vanuatu, on the morning of the 25th. Instead of passing the day with their families, the team climbed down a 1200ft cliff to get close to a flowing lake of lava. (Photo by Bradley Ambrose/Caters News)

At 10,582 square kilometres, the Bolivian salt flats – otherwise known as Salar de Uyuni – are the largest on the planet and contain between 50 and 70% of the world’s lithium reserves. After exploring Chile and Argentina, photographer Joel Santos decided to travel to Bolivia in January 2017 to check the salt flats off his bucket list. With an electrical storm rolling in, Joel and his two travelling companions were the only souls left on the vast flats and captured the eerie flats without a person in sight. (Photo by Joel Santos/Barcroft Images)

Taronga's first female elephant calf explores the paddock with her mother Pak Boon at Taronga Zoo on November 3, 2010 in Sydney, Australia. The 120kg elephant was born at 1:12am and is Taronga's first female calf and fifth born to The Australian Conservation Management Plan for endangered elephants. The calf will be given a Thai name to reflect the herds' cultural origin. (Photo by Brendon Thorne/Getty Images)

Artist C. K. Wilde creates intricate collage compositions using pieces of paper currency from all over the world. His collages have referenced subjects ranging from space exploration, to mythology, religion, slavery, ecology, the history of warfare, the history of money, and art history. Photo: “Great Crash”. (Photo by C. K. Wilde)

“Ashes and Snow by Canadian artist Gregory Colbert is an installation of photographic artworks, films, and a novel in letters that travels in the Nomadic Museum, a temporary structure built exclusively to house the exhibition. The work explores the shared poetic sensibilities of human beings and animals”. – Wikipedia. (Photo by Gregory Colbert)

The couple freedivers Eusebio and Christina Saeyns de Santamaria, known as «One ocean One breath», exploring the pond around the world, plunging into the water deep down in one breath.

This watering hole is the social hub of the veldt; the scrubby grasslands that stretch across Namibia. The scorched earth supports sometimes fragile populations of magnificent wildlife – from endangered predators to plentiful herds of game. But these gentle giraffes and elephants need to be careful: lions don’t sleep at night, they hunt! The spectacular starscape above southern Africa is unchanged since explorers first mapped the continent. The photographer, Pietro Olivetta from Italy, said he had to be patient to capture these shots – but it was worth the wait. (Photo by Pietro Olivetta/Caters News)

Climbers “painted” the Matterhorn red this week to celebrate a special anniversary. A group of mountaineers left red beacons along the route of the famous climb, which is one of the highest mountains in the Alps, and as nightfall came the imposing mountain came alive with colour. The event was organised by clothing brand Mammut to celebrate the 150th anniversary of the first explorers to scale the mountain. (Photo by MSN UK/Mammut)