A masked reveller parades through the streets on the first day of the carnival season in Lucerne, Switzerland, 12 February 2015. In the background the well known Kappellbruecke bridge. (Photo by Alexandra Wey/EPA)

An art installation formed with milk churns, made by land art artist Gerard Benoit a la Guillaume, is seen at the Chenau de Mayen in the resort of Leysin, Switzerland August 7, 2015. More than 80 milk churns were placed between the Tour d'Ai and the Tour de Mayen summits at an altitude of 2,000 meters (6,561 feet) above sea level under the direction of the artist, to be photographed for his ongoing art project entitled “Milk churns without borders”. (Photo by Denis Balibouse/Reuters)

A boy shouts after catching a trout during a trout catching contest in Hwacheon, South Korea, Saturday, January 6, 2018. The contest is part of an annual ice festival which draws over 1,000,000 visitors every year. (Photo by Ahn Young-joon/AP Photo)

Women carry gas cylinders to fill them at a distribution point in Cairo January 19, 2015. Egypt is going through its worst energy crisis in decades and is seeking fresh sources of natural gas, which powers most of its homes and factories. (Photo by Mohamed Abd El Ghany/Reuters)

On Keo Wa, 25, carries her 9-month-old baby while working at a banana plantation operated by a Chinese company in the province of Bokeo in Laos April 24, 2017. (Photo by Jorge Silva/Reuters)

A man sits waiting for a train on the London Underground in 1890, when the platform floors were still made from wooden floorboards. (Photo by Hi-Story/Alamy Stock Photo)

A runner taking part in the 38th Annual Empire State Building Run-Up is pictured arriving on the 86th floor in the Manhattan borough of New York February 4, 2015. (Photo by Carlo Allegri/Reuters)

Participants in the 18th Annual “No Pants Subway Ride” travel in the subway on January 13, 2019 in New York. The “No Pants Subway Ride” is an annual event started in 2002 by Improv Everywhere in New York, the goal of which is for riders on the subway train to dress in normal winter clothes without pants while keeping a straight face. (Photo by Johannes Eisele/AFP Photo)