Andrey Karr from Western Riders Slacklines at sunset above big waves in Nazare, Portugal on December 27, 2017. (Photo by Aidan Williams/National Geographic Travel Photographer of the Year Contest)

Dancer Megan changes costume as she performs in the review “Feerie” at the Moulin Rouge in Paris, France, July 3, 2018. Each show requires 1,000 outfits, all crafted in the workshops that have been supplying the Moulin Rouge for decades. Each dancer has to make between 10 and 15 costume changes per show, with about 90 seconds to complete each one before they have to be back out on stage. (Photo by Philippe Wojazer/Reuters)

Muhannad al-Kadiri (R),18, and Ibrahim Eid, 16, demonstrate their Parkour skills over a military vehicle in the rebel-held city of Inkhil, west of Deraa, Syria, February 4, 2017. (Photo by Alaa Al-Faqir/Reuters)

A Palestinian youth demonstrates his parkour skills on a street in Gaza City, January 15, 2016. (Photo by Suhaib Salem/Reuters)

In this Wednesday, November 15, 2012 file photo, a young girl in her colorful dress reaches out to greet a Pakistani policeman securing the road outside Kainat Riaz's home in Mingora, Swat Valley, Pakistan. (Photo by Anja Niedringhaus/AP Photo)

A general view of Hong Kong's business district is seen Thursday, August 1, 2013. (Photo by Vincent Yu/AP Photo)

A Palestinian boy herds sheep in front of the ruins of Yasser Arafat International Airport, which was bombed by Israel in the past, in Rafah in the southern Gaza Strip February 5, 2016. Nabil Shurafa's travel agency in Gaza was once packed with clients booking flights to London, Paris, New York or cities across the Arab world. These days, he's lucky if anyone comes in, as so few people can get out. (Photo by Ibraheem Abu Mustafa/Reuters)

An Afghan journalist takes a “selfie” as U.S. President Barack Obama (R) holds a joint news conference with Afghanistan's President Ashraf Ghani (C) at the White House in Washington March 24, 2015. (Photo by Jonathan Ernst/Reuters)