A participant of the Castle Party festival poses for picture as a man walks past in Bolkow, southwestern Poland, July 16, 2015. The annual festival features around 50 musicians and artists playing on various stage Gothic rock and other styles of the dark music subculture. Outside Germany, it is one of the biggest festival with this genre of music, the event attracts regular international audience of up to 5000, the organizers said. (Photo by Kacper Pempel/Reuters)

A Hindu devotee wearing a t-shirt printed with a portrait of Lord Shiva takes a holy dip while participating in the “Bol Bom” pilgrimage in Kathmandu August 10, 2015. The faithful, chanting the name of Lord Shiva, run about 15 km (9 miles) barefooted toward Pashupatinath temple seeking good health, wealth and happiness. (Photo by Navesh Chitrakar/Reuters)

A Snowboarder participates in a waterslide contest, which consists of gliding over a water pool embedded in snow, during the closing event of the ski resort of Nendaz, southwestern Switzerland, Monday, April 21, 2014. (Photo by Maxime Schmid/AP Photo/Keystone)

Pakistani brides attend a mass marriage ceremony in Karachi late March 26, 2013. Some 110 couples participated in the mass wedding ceremony organised by a local charity welfare trust Al Ghousia. (Photo by Asif Hassan/AFP Photo)

A competitor participates at the World Pole Dancing Championship 2012 held at the Volkshaus on November 10, 2012 in Zurich, Switzerland. The public's perception of pole dancing has recently changed to become a popular sport combining physical strength, technique and choreography. (Photo by Harold Cunningham)

Dhruva Aliman does a back somersault as he dismounts from a slackline on the beach at Santa Monica, California on October 19, 2014. Slackline is a balance sport where a line of webbing is adjusted at different levels of tension between two anchor points and participants (called slackers) perform tricks and stunts including somersaults. (Photo by Mark Ralston/AFP Photo)

Students participate in an earthquake drill in their school in Santiago, November 13, 2014. Around one million people, which included students, teachers and parents, took part on Thursday in a drill that simulated a fictitious earthquake of a magnitude of 8.8 on the Richter scale, according to organizers. (Photo by Ivan Alvarado/Reuters)

Participants dressed as Vikings carry torches as they march in procession before burning their viking galley ship at the culmination of the annual Up Helly Aa festival in Lerwick, Shetland Islands, on January 31, 2017. (Photo by Andy Buchanan/AFP Photo)