A German special anti-tank gun is ready to fire during the army maneuvers in Silesia, Poland, on September 22, 1928. (Photo by AP Photo)

Mt.Huanshan, or Mount Hua is one of the five sacred mountains in China. The other four are Taishan in Shandong, Songshan in Henan, Hengshan in Shanxi and Hengshan in Hunan.
Mt. Huashan is reputed as the most precipitous of the five.

Iranian-Kurdish female fighters hold their weapons during a battle with Islamic State militants in Bashiqa, near Mosul, Iraq on November 3, 2016. (Photo by Ahmed Jadallah/Reuters)

Members of rival teams fight with oranges during an annual carnival battle in the northern Italian town of Ivrea, Italy on February 11, 2018. Established in 1808, the Carnival of Ivrea is one of the oldest and most particular festivals in the world. (Photo by Alessandro Bianchi/Reuters)

A model wears a dress made out of recycled material during a show organised by LGBT fashion designers to battles discrimination in Phnom Penh, Cambodia, October 24, 2018. (Photo by Samrang Pring/Reuters)

Iraqi paramilitary troops fire towards Islamic State militants during a battle with Islamic State militants on the outskirts of the ancient city of Hatra near Mosul,Iraq April 26, 2017. (Photo by Reuters/Stringer)

A member of Iraqi rapid response forces fires a rocket launcher during a battle with Islamic State militants in the district of Yarimja in southern Mosul, Iraq, January 18, 2017. (Photo by Alaa Al-Marjani/Reuters)

Chinese special policemen rank in a line of battle during an anti-terror drill at a training base of Chengdu Armed Police Headquarters on September 28, 2005 in Chengdu of Sichuan Province, China. (Photo by China Photos/Getty Images)