A line of soldiers firing handguns during a training session, circa 1920. (Photo by Keystone). P.S. All pictures are presented in high resolution.

Film actress Audrey Hepburn (1929–1993) on a film set with her pet poodle, circa 1960. (Photo by Hulton Archive/Getty Images)

Queen Elizabeth II (as Princess Elizabeth) writing at her desk in Windsor Castle, Berkshire. (Photo by Lisa Sheridan/Studio Lisa/Getty Images). 30th May 1944

Two female holidaymakers relax on an unidentified beach of England, September 21, 1940, as a soldier, eyes straight ahead, stands guard at a barrier built as a defense against possible invasion by Germany. (Photo by AP Photo)

Mariachi musicians prepare to perform to celebrate the Day of the Virgin of Guadalupe outside the Basilica of Guadalupe in San Salvador, El Salvador December 11, 2015. (Photo by Jose Cabezas/Reuters)

A close up of a caracal lynx's face looking into a camera on January 2014 in Western Cape, South Africa. (Photo by Dale Morris/Barcroft Media)

Israeli soldiers of the Search and Rescue brigade take part in a training session in Ben Shemen forest, near the city of Modi'in May 23, 2016. (Photo by Amir Cohen/Reuters)

Chantel Sydnor participates in the annual Sturgis Motorcycle Rally in Sturgis, South Dakota, August 4, 2015. This year marks the 75th anniversary of the rally expected to draw hundreds of thousands of motorcycle enthusiasts from around the world for events throughout the week-long festival, according to organizers. (Photo by Kristina Barker/Reuters)