This photo taken November 10, 2015 shows homeless street children sleeping in a park in Manila. The Philippines has swept 20,000 homeless from the streets, cancelled hundreds of flights and declared public holidays in Manila to ensure a safe and efficient summit of 21 world leaders next week, officials say. (Photo by Jay Directo/AFP Photo)

Vehicles are burning as thousands of people take to the streets during the May Day demonstrations on May 1, 2018 in Paris, France. This month celebrates the 50th anniversary of May 68 when France seen millions of students and striking workers, come onto the streets in demonstrations that changed the country. (Photo by Jeff J. Mitchell/Getty Images)

“Slow”. A calm cow in the messy streets of Jodhpur. Photo location: India. (Photo and caption by Matthias Troeger/National Geographic Photo Contest)

A man crosses Canal Street in the wind and rain from Hurricane Isaac August 29, 2012. (Photo by David J. Phillip/Associated Press)

People cross the street in central Pyongyang, North Korea May 4, 2016. (Photo by Damir Sagolj/Reuters)

People use a board to travel on a flooded street after heavy rainfall in Baghdad, Iraq, October 31 2015. (Photo by Ahmed Saad/Reuters)

A homeless man rests on the side of a street at the old quarter of Yemen's capital Sanaa November 27, 2015. (Photo by Khaled Abdullah/Reuters)