Jan Kara (R) and Jan Holan pedal their boat, made with plastic bottles, on the Elbe river near Kostelec nad Labem July 15, 2014. Jan Kara, a 22-year-old student, and Jakub Bures, a 22-year-old car mechanic, built the 10-metre (32.8-feet) long boat from 5000 plastic bottles strapped to a wooden frame. (Photo by David W. Cerny/Reuters)

Romanian soldiers take part in a joint military exercise with NATO members, called “Agile Spirit 2015” at the Vaziani military base outside Tbilisi, Georgia, July 21, 2015. Georgian soldiers along with U.S. marines and platoon-size units from Bulgaria, Latvia, Lithuania and Romania are taking part in the exercises at the Vaziani military base outside Tbilisi. (Photo by David Mdzinarishvili/Reuters)

People walk past debris on May 3, 2015 in Bhaktapur, Nepal. A major 7.8 earthquake hit Kathmandu mid-day on Saturday, and was followed by multiple aftershocks that triggered avalanches on Mt. Everest that buried mountain climbers in their base camps. (Photo by David Ramos/Getty Images)

Attendees wear a cardboard “Facebox” at the 2017 South By Southwest (SXSW) Interactive Festival at the Austin Convention Center in Austin, Texas, U.S., on Monday, March 13, 2017. The SXSW Interactive Festival features a variety of tracks that allow attendees to explore what's next in the worlds of entertainment, culture, and technology. (Photo by David Paul Morris/Bloomberg)

A fan wipes her lip after she was hit on the mouth by a foul ball hit by Kansas City Royals' Brandon Moss during the third inning of the Royals' baseball game against the Chicago White Sox, Friday, September 22, 2017, in Chicago. (Photo by David Banks/AP Photo)

A fisherman carries a silver carp during a traditional fish haul at the Horusicky pond near the town of Veseli nad Luznici, Czech Republic, Tuesday, October 24, 2017. Each autumn, Czech fishermen get to serious business of a century-long tradition of catching carp for Christmas markets. Southern Bohemia, where the Horusicky pond is located, with its elaborate network of ponds is at the center of the local carp universe. (Photo by Petr David Josek/AP Photo)

A truck remains mired in mud and debris on State Route 58 near Tehachapi, California, about 60 miles (97 km) outside of Los Angeles October 17, 2015. A mudslide on Thursday left nearly 200 vehicles, including 75 semi-trailer trucks, stuck in up to five feet of mud, local sheriff's spokesman Ray Pruitt said. (Photo by David McNew/Reuters)

A local man looks at a church on top of the Katskhi Pillar, rock mass about 40 meters high, in the village of Katskhi, Georgia, November 27, 2015. The church, built in the ninth century, was later abandoned and it collapsed but was rebuilt in 2003, according to local media. (Photo by David Mdzinarishvili/Reuters)