The Flying Bull's P-38 Lockheed Lightning N25Y / 13 – Red Bull – Flying Legends Airshow 2012 Duxford (Photo by Rob Lovesey)

A supporter of “Si” vote cries after the nation voted “NO” in a referendum on a peace deal between the government and Revolutionary Armed Forces of Colombia (FARC) rebels, at Bolivar Square in Bogota, Colombia, October 2, 2016. (Photo by John Vizcaino/Reuters)

This August 15, 2016 photo shows two portraits Carolina, one of her holding a weapon while in her uniform for the Revolutionary Armed Forces of Colombia (FARC) 49th front, and in civilian clothing at a guerrilla camp in the southern jungle of Putumayo, Colombia. Carolina, 18, said she has spent three years in the FARC and would like to study engineering after demobilizing as part of a peace deal with Colombia's government. (Photo by Fernando Vergara/AP Photo)

A pro-Russian rebel guards a captured former Ukrainian Army checkpoint outside Vuhlehirsk, Donetsk region, eastern Ukraine, Thursday, February 5, 2015. The rebels have closed in around the town in a strategy they triumphantly refer to as the Debaltseve cauldron. Separatists recently burst through government lines in the rural settlement of Vuhlehirsk. (Photo by Vadim Braydov/AP Photo)

A man works inside a bakery in the rebel-controlled area of Maaret al-Numan town in Idlib province, Syria December 17, 2015. (Photo by Khalil Ashawi/Reuters)

Female soldiers of the self-proclaimed Donetsk People's Republic hold flowers backstage during a beauty pageant to mark International Women's Day in Donetsk, March 7, 2015. (Photo by Marko Djurica/Reuters)

A female member of the Ahbab Al-Mustafa Battalion holds a gun as she undergoes military training in Aleppo's Salaheddine district, June 24, 2013. (Photo by Muzaffar Salman/Reuters)

Most pet cats will become timid or defensive when outdoors, but not Millie – after being adopted by her mountain-climbing owner Craig Armstrong, Millie has become a feline hiking and mountain-climbing legend.