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)

Sinabung mount spews ash to the air during an eruption near from Karo, North Sumatra on January 7, 2014. An Indonesian volcano that has erupted relentlessly for months shot volcanic ash into the air 30 times on January 4, forcing further evacuations with more than 20,000 people now displaced, an official said. (Photo by Sutanta Aditya/AFP Photo)

A villager run as Mount Sinabung erupt at Sigarang-Garang village in Karo district, Indonesia's North Sumatra province, February 1, 2014. Four people died and more than 28, 000 villagers have been evacuated since authorities raised the alert status for the volcano to the highest level in November 2013, local media reported on Saturday. (Photo by Reuters/Stringer)

A terrace of a house is covered with ash after the eruption of the Fuego volcano at San Miguel Los Lotes in Escuintla, Guatemala, June 6, 2018. (Photo by Carlos Jasso/Reuters)

A woman takes a picture with her mobile phone from Caviahue, Neuquen province, Argentina, some 1500 km southwest of Buenos Aires, of the Copahue volcano spewing ashes on December 22, 2012. The authorities of Chile and Argentina issued yellow alerts due to the eruption of the Copahue volcano, placed in the border between both countries. (Photo by Antonio Huglich/AFP Photo)

General view of Chilean Calbuco volcano from Puerto Montt, located at 1000 km southern Santiago de Chile, Chile, 22 April 2015. Due to the eruption of the volcano with a smoke column 20 km high, authorities declared a red alert and ordered the evacuation of around 1500 inhabitants of Ensenada, Alerce, Colonia Río Sur and Correntoso towns. (Photo by Alex Vidal Brecas/EPA)

Waves crash over lava as it flows into the ocean near Volcanoes National Park in Kalapana, Hawaii on November 27, 2012. A volcano on Hawaii's largest island is spilling lava into the ocean, creating a rare and spectacular fusion of steam and waves that officials said on Tuesday could attract thrill seeking visitors if it continues. (Photo by Hugh Gentry/Reuters)

Indonesian activists covered with sludge from the mud volcano hold a protest during five year anniversary of the Sidoarjo mud eruption on May 29, 2011 in the subdistrict of Porong in Sidoarjo, East Java, Indonesia. (Photo by Ulet Ifansasti/Getty Images)