Alex Plunkett, left, and Sean Hart, both of Arlington, Va., join hundreds participating in the annual International Pillow Fight Day on April 5. Massive pillow fights broke out on the Mall in Washington and in cities around the world. (Photo by Marvin Joseph/The Washington Post)

Aerial photo taken on March 4, 2017 shows cole flower fields in Luoping County, southwest China's Yunnan Province. (Photo by Xinhua/Barcroft Images)

A reveller plays with tomato pulp during the annual Tomatina festival in Bunol, near Valencia, Spain on August 29, 2018. As every year on the last Wednesday of August, thousands of people visit the small village of Bunol to attend the Tomatina, a battle in which tons of ripe tomatoes are used as weapons. This year, a total of 145 tons of ripe tomatoes will be thrown between more than 22,000 participants. (Photo by Heino Kalis/Reuters)

Hao Han (8), Shaolin kung fu student and child actor. Shaolin Monastery, Henan. (Photo by Mathias Braschler and Monika Fischer)

Fisherwomen laying barrels with salt in preparation for herring curing, 1937. (Photo by Topical Press Agency)

Attnedees dressed in Zombie outfits walk down the Gaslamp Quarter outside of the 2015 Comic-Con International in San Diego, California July 8, 2015. (Photo by Sandy Huffaker/Reuters)

In 2012 in Kiev will pass European Football Championship. The history of Kiev, the largest city and the capital of Ukraine, is documented as going back at least 1400 years...

A Ugandan soldier, part of the 9,000-strong African Union Mission in Somalia, (AMISOM) walks through the Banadir soccer stadium on August 15, 2011 in Mogadishu, Somalia. The stadium, Somalia's largest soccer facility, had been under control by Islamic extremist Shabab militants for the past two years until they withdrew from the capital more than a week ago. (Photo by John Moore/Getty Images)