A US Marine leads two Viet Cong suspects in restraints during the Tet Offensive on February 20, 1967. (Photo by Bettmann Archive/Getty Images)

“The Tonight Show” host Jimmy Fallon, center, exits the water during the Chicago Polar Plunge, Sunday, March 2, 2014, in Chicago. Fallon joined Chicago Mayor Rahm Emanuel in the event. (Photo by Andrew A. Nelles/AP Photo)

A participant prepares for the Red Bull Air Race World Championships in Abu Dhabi, United Arab Emirates on February 6, 2017. (Photo by Red Bull Content Pool/SIPA Press/Rex Features/Shutterstock)

A woman promotes a go-go dance bar in Pattaya, Thailand March 25, 2017. With mascots dressed as smiling fish and a police rock band, Thai authorities launched a “Happy Zone” at the weekend to improve the image of a city notorious for sеx tourism. Stung by foreign headlines portraying the seaside resort of Pattaya as “Sin City” and “The World’s Sеx Capital”, Thailand’s junta has begun a new effort to re-brand it. Businesses in the Happy Zone are asked to make the area feel safer, there are increased security patrols, police launched a mobile phone app for visitors to summon them if an emergency occurs. (Photo by Jorge Silva/Reuters)

Girls dressed in traditional costumes run as men throw water on them as part of Easter celebrations during a presentation to the media in Mezokovesd, Hungary, April 13, 2017. (Photo by Laszlo Balogh/Reuters)

A girl lights a candle as she marks the anniversary of 2015 Nepal earthquake, at Boudhanath stupa in Kathmandu, Nepal April 25, 2017. (Photo by Navesh Chitrakar/Reuters)

Ukrainians jump over a fire in Kiev, Ukraine, 06 July 2017, as they celebrate the traditional pagan holiday of Ivana Kupala. Ivana Kupala is celebrated, during the summer solstice, on the shortest night of the year, marking the beginning of summer and is celebrated in Ukraine, Belarus, Poland and Russia on the night of 06 July. People sing and dance around bonfires, play games and perform traditional rituals. Young people jump over bonfires in order to test their bravery. Couples holding hands jump over the flames to test their love. If the couple does not succeed it is predicted to split up. Traditionally, children and young unmarried women wear wreaths of wild flowers on their heads to symbolize purity. (Photo by Sergey Dolzhenko/EPA)

Revellers wearing lanterns parade through the streets during the carnival procession of Basel, Switzerland, 15 February 2016. The traditional Morgestraich starting Monday morning after Ash Wednesday at 4 a.m. marks the kick-off of the Carnival of Basel. (Photo by Patrick Seeger/EPA)