In this photo taken on Saturday, November 16, 2013, Mt. Etna, Europe's most active volcano, spews lava during an eruption as seen from Acireale, near the Sicilian town of Catania, Italy. (Photo by Carmelo Imbesi/AP Photo)

A resident carries a gas canister as an ash cloud hovers above during an eruption of Mount Sinabung volcano at Tiga Serangkai village in Karo Regency, North Sumatra province, Indonesia June 24, 2015. More than 10,000 people from 12 villages, who are living around the slopes of Mount Sinabung, left their homes and moved to refugee camps, local media reported. (Photo by Reuters/Beawiharta)

A Hindu villager rides a motorcycle past an altar ahead of the annual Kasada festival at the Mount Bromo in Indonesia's East Java province, July 30, 2015. The Kasada festival will be held on August 1, when the worshippers throw offerings such as livestock and other crops into the volcanic crater of Mount Bromo to give thanks to the Hindu gods for ensuring their safety and prosperity. (Photo by Reuters/Beawiharta)

Students from St Andrew's University indulge in a tradition of covering themselves with foam to honour the “academic family” on October 20, 2014, in St Andrews, Scotland. Every November the “raisin weekend” which is held in the university's Lower College Lawn, is celebrated and a gift of raisins (now foam) is traditionally given by first year students to their elders as a thank you for their guidance and in exchange they receive a receipt in Latin. (Photo by Jeff J. Mitchell/Getty Images)

Twenty five life-size donkeys have been given pride of place in St Paul's Cathedral as part of an interfaith exhibition. They've been painted by Egyptian and Western artists, to show solidarity for the people of Egypt. Photo: Artist painted donkey statues are displayed in the “Caravan” exhibition on August 30, 2013 in London, England. (Photo by Peter Macdiarmid)

Australian knight Philip Leitch (R) has a floral basket on his helmet smashed by an opponent at the St Ives Medieval Fair in Sydney, one of the largest of its kind in Australia, September 25, 2016. (Photo by Jason Reed/Reuters)

A group of young women have 'a bit of a do' for Oxfam at St Pancras International and enjoy a screening of the nation's favourite chick-flick Dirty Dancing on February 28, 2011 in London, England. Oxfam is calling on women across the UK to get together with their female friends in March to celebrate women's achievements for the 100th anniversary of International Women's Day (March 8, 2011) and raise money to support their work with women living in poverty. www.oxfam.org.uk/do (Photo by Ian Gavan/Getty Images for Oxfam). LONDON, ENGLAND – FEBRUARY 28

A participant dressed in a traditional devil costume walks from house to house during the traditional St. Nicholas parade on December 3, 2016 in village of Francova Lhota, Czech Republic. This type of parade is one of the most popular age-old traditions in a few villages in the Wallachia region of Eastern Czech Republic. St. Nicholas and company roam the streets going from house to house, for two or three days as St. Nicholas gives sweets and tiny gifts as a present to children and the devils get up to mischief. (Photo by Matej Divizna/Getty Images)