Dr. P.A. Smithe was sent by the American Red Cross as a doctor and surgeon to work at a hospital in Vienna. He sailed to Europe in December 1915 and returned home in August 1916, according to his daughter, who donated his images to the National World War I Museum. Photo: Turkish army, including cavalry, infantry and artillery. (Photo by Dr. P.A. Smithe/National World War I Museum, Kansas City, Mo.)

An Afghan child practices walking with his new prosthesis at the International Committee of the Red Cross (ICRC), orthopedic center on September 10, 2011 in Kabul, Afghanistan. After more than 30 years of war and a decade since the 9/11 attacks in the United States, thousands of Afghans, both military and civilian, continue to pay a heavy price from the conflict. The ICRC center makes prosthetics for amputees and helps them, as well as Afghans with spinal injuries and children with congenital birth defects, to learn to walk. (Photo by John Moore/Getty Images)

A catholic faithful smeared in burnt oil, takes part in the opening of the ten-day celebration of the Santo Domingo de Guzman festival in Managua, on August 1, 2019. In Central America the black devil, or El Cadejo, is an evil dog-like spirit with glowing red eyes that locals believe eats new born puppies. (Photo by Inti Ocon/AFP Photo)

Stunning silhouettes under European cities reveal the size and splendor of the continent’s urban foundations. Photographer and content-manager Anna Arinova, 28, from Moscow, captured the awe-inspiring labyrinths in Russia and Germany. Here: Regenwurmlager, Poland. The Regenwurmlager is an extensive underground fortification area constructed by Germany in 1920s-1940s, now in western Poland, near the city of Międzyrzecz. (Photo by Anna Arinova/Caters News)

Aerial shots always amaze us by their magnificence. Human-sized footprints look like ant trails, trees resemble little pieces of broccoli, and landscapes are transformed into breathtaking images, which look like something that can be seen under a microscope. This set of pictures features surreal aerial shots of Botswana taken by Zack Seckler. In the past, to make these kinds of shots, someone had to go up in a helicopter to take a picture. However, today, such images can be easily made using quadcopters, such as DJI Phantom or any other. Thanks to the new technology, we are able to view our world in new ways, allowing us to better appreciate its complexity and beauty. (Photo by Zack Seckler)

Hugo Belleri (L), a three-year-old boy and the youngest Gilles of Binche, takes part in the parade of Young Gilles of Binche during the carnival event in Binche February 17, 2015. The Binche carnival, a UNESCO World Heritage event, is the biggest and the liveliest annual event in Belgium. Up to 1,000 Gilles parade in the city centre of Binche, wearing a red, yellow and black medieval costume hung with bells and decorated with fluffy lace at the neck, wrists and ankles. (Photo by Yves Herman/Reuters)

Local villagers prepare to bury the body of elephant Hemantha during a religious ceremony at a Buddhist temple in Colombo March 15, 2016. Elephant Hemantha, which died from injuries to its feet, was under medical treatment for the last six months. The elephant used to march at street parades during festivals held by the temple. Elephant Hemantha died at age 23. Wild elephants have long lifespans, reaching 60–70 years of age. (Photo by Dinuka Liyanawatte/Reuters)

A girl collects drinking water at Dala river outside Yangon, Myanmar March 3, 2016. Some 650 million people, or one in 10 of the world's population, have no access to safe water, putting them at risk of infectious diseases and premature death. Dirty water and poor sanitation can cause severe diarrhoeal diseases in children, killing 900 under-five a day across the world, according to United Nations estimates. (Photo by Soe Zeya Tun/Reuters)