An Egyptian boy holds a camel at the Berqash camel market northeast of Cairo, on August 17, 2018. Muslims across the world are preparing for the Eid al-Adha holiday when custom requires the faithful to make a sacrifice. (Photo by Khaled Desouki/AFP Photo)

Spain's Lidia Rodriguez, Spain's Marta Garcia and Spain's Raquel Roy compete in the Kata team female final during the 24th Karate World Championships at the WiZink center in Madrid on November 11, 2018. (Photo by Javier Soriano/AFP Photo)

As the world marks International Women's Day on Wednesday, whose theme this year focuses on “women in the changing world of work”, the Israeli military says it is ahead of the curve in providing combat roles for female soldiers. Here: A female Israeli soldier from the Haraam artillery battalion fixes her hair in the women's living quarters at a military base in the Israeli-occupied Golan Heights March 1, 2017. (Photo by Nir Elias/Reuters)

Vietnam’s Son Doong cave, the largest in the world, could hold a 40-story skyscraper inside. The pristine ecosystem has its own river and jungle. Despite its size, Son Doong wasn’t discovered until 1991. It was lost again for nearly two decades and was fully explored for the first time in 2009. (Photo by Jason Speth/HuffPost)

A dancer performs before a judging panel during the World Irish Dancing Championships in Dublin, Ireland on April 11, 2017. The April 9-16 event draws some 5,000 performers from Ireland and overseas, including from both the Irish diaspora in places like the United States and Australia as well as less likely countries such as Russia and Japan. (Photo by Clodagh Kilcoyne/Reuters)

Fans dressed in Spider-Man outfits gather at a promotional event for the forthcoming “Spider-Man: Homecoming” movie at the Art Science Museum in Singapore on June 7, 2017. The movie will be shown in cinemas around the world from July 5 onwards. (Photo by Toh Ting Wei/AFP Photo)

Canada's Marissa Papaconstantinou makes her way to the finish line after falling in the Women's 200m T44 Final during day ten of the IPC World ParaAthletics Championships 2017 at London Stadium on July 23, 2017 in London, England. (Photo by Peter Cziborra/Reuters)

Photochromes are vibrant and nuanced prints hand-coloured from black-and-white negatives. Created using a process pioneered in the 1880s, these images offer a fascinating insight into the world when colour photography was still in its infancy. A Tour of the World in Photochromes is at the Swiss Camera Museum, Vevey, until 21 August. Here: Street food in the Strada del Porto in Naples, Italy, 1899. (Photo by Swiss Camera Museum/The Guardian)