Revelers dance and shout as they listen to music, in front of the main stage, during the 21st Woodstock Festival in Kostrzyn-upon-Odra, Poland July 31, 2015. An estimated 200,000 people attended the ongoing festival, a brainchild of Polish journalist and social campaigner Jerzy Owsiak, on Friday. Owsiak initiated the event to say thank you to those who donated money to his GOCC charity organisation that delivers medical care for children. (Photo by Kacper Pempel/Reuters)

Festival-goers wash on Shipyard Island, the venue of the 24th Sziget (Island) Festival in Northern Budapest, Hungary, 15 August 2016. The venue, one of the biggest cultural events of Europe, offers art exhibitions, theatrical and circus performances and above all music concerts from 10 to 17 August. (Photo by Szabó Gábor/Origo.hu)

Photographer Han Youngsoo captured the ordinary people of Korea as the country emerged from war into an age of prosperity. Han Youngsoo: Photographs of Seoul 1956–63 is at the International Center of Photography (ICP), Jersey City, New Jersey, until June 9, 2017. Here: Seoul, Korea. (Photo by Han Youngsoo/The Guardian)

Independent miners transport llamas to sacrifice them for good fortune during the year as part of Andean carnival celebrations, outside the Mina Itos on the outskirts of Oruro, Bolivia February 24, 2017. (Photo by David Mercado/Reuters)

A member of the USA Knights team is seen wearing a face-like helmet shield during the International Medieval Combat championships at the castle of Belmonte, May 4, 2014, in Belmonte, Spain. The steel armor the knights wear can cost up to $10,000 and weigh 80 pounds. (Photo by Juan Naharro Gimenez/Getty Images)

A photographer has shared his stunning gallery of African sunrises and sunsets. Paul Goldstein says he has spent years trying to photograph the perfect beginning and ending of the Masai Mara day. Thanks to his role as guide for Exodus Travels, there have been countless opportunities to document the beautiful natural spectacle. Photo: “African Fire”: Ostrich at sunset. (Photo by Paul Goldstein/Rex Features)

A girl rides on a train as she takes part in the first edition of the No Pants Subway Ride in Bucharest, Romania, Sunday, January 11, 2015. The No Pants Subway Ride is an annual which was started in 2002 by Improv Everywhere in New York, the goal is for riders to get on the subway train dressed in normal winter clothes without pants and keep a straight face. (Photo by Vadim Ghirda/AP Photo)

Vancouver B.C. April 20, 2014 Big Day to celebrate as thousand gathered in front of Vancouver Art Gallery to take part in the 420 Marijuana smoke in here in Vancouver on April 20, 2014. Here lots of free “joints” ready for the big moment. (Photo by Mark van Manen/PNG Staff Photographer/Ian Austin Province News/Vancouver Sun News & Web stories)