A woman is supported by two men while crossing a river, north of Idomeni, Greece, as migrants attempt to reach Macedonia on a route that would bypass the border fence, Monday, March 14, 2016. Hundreds of migrants and refugees walked out of an overcrowded camp on the Greek-Macedonian border Monday, determined to use a dangerous crossing to head north. (Photo by Vadim Ghirda/AP Photo)

Participants in traditional dress ride on horseback as they enjoy the atmosphere at the Feria de Abril (April's Fair) on April 12, 2016 in Seville, Spain. The Feria de Abril has a history that dates back to 1857 and takes place a fortnight after Easter each year. The origin of the fair was a cattle market but the event quickly turned its goal from commerce to having fun. More than 1 million local and international participants are expected to attend the Feria de Abril. (Photo by David Ramos/Getty Images)

Korean People's Army (KPA) soldiers march during a mass rally on Kim Il Sung square in Pyongyang on September 9, 2018. Thousands of North Korean troops followed by artillery and tanks paraded through Pyongyang on September 9 as the nuclear-armed country celebrated its 70th birthday, but it refrained from displaying the intercontinental ballistic missiles that have seen it hit with sanctions. (Photo by Ed Jones/AFP Photo)

Eagle Prime (MK3), a giant robot by MegaBots Inc. which manufactures giant piloted humanoid fighting robots headquartered in Berkeley, California on October 18, 2017. (Photo by Courtesy Michael Mauldin/Reuters/MegaBots Inc)

Children are engulfed by foam during the Bubble Show event in Beijing, China, Sunday, June 26, 2016. Thousands of residents enjoy colored foam churned out by machines along a running track at the event designed for children and parents' interaction. (Photo by Ng Han Guan/AP Photo)

Just a week before Rio de Janeiro hosts South America's first Olympics, city residents expressed mixed feelings about the cost and security of the Games, while holding out hope they will bring joy to a nation facing economic and political crises. The conflicted thoughts mirror a recent survey by the Datafolha polling group showing that half of Brazilians were opposed to holding the Games, while 63 percent think the costs of hosting the event will outweigh benefits. (Photo by Pilar Olivares/Reuters)

Participants wearing historical attire compete on historical high wheel Penny Farthing bicycles in the traditional 'One Mile Race' at Letna Park in Prague, Czech Republic, November 7, 2015. The meeting of Penny Farthing bicycles is taking place for the 22th time. (Photo by Filip Singer/EPA)

Filipino Muslims ride on top of a vehicle as they celebrate the end of the holy month of Ramadan in Cotabato city, in southern Philippines, July 16, 2015. Picture taken July 16, 2015. (Photo by Marconi Navales/Reuters)