U.S. Army soldiers from the 2-82 Field Artillery, 3rd Brigade, 1st Cavalry Division, wait to load onto their armored vehicles as they prepare to convoy to Kuwait from Camp Adder in Iraq on December 7, 2011 at Camp Adder, near Nasiriyah, Iraq. (Photo by Joe Raedle/Getty Images)

South Korean special warfare command soldiers participate in winter military training exercise on January 11, 2012 in Pyeongchang-gun, South Korea. The South Korean troops train in temperatures below -20 degrees celsius to defend the country against any possible attacks from North Korea. (Photo by Chung Sung-Jun/Getty Images)

Students participate in an earthquake drill in their school in Santiago, November 13, 2014. Around one million people, which included students, teachers and parents, took part on Thursday in a drill that simulated a fictitious earthquake of a magnitude of 8.8 on the Richter scale, according to organizers. (Photo by Ivan Alvarado/Reuters)

“Miniatur Wunderland is a model railway attraction in Hamburg, Germany and the largest of its kind in the world. As of January 2011, the railway consists of 12,000 metres (39,370 ft) of track in HO scale, divided into seven sections: Harz, the fictitious city of Knuffingen, the Alps and Austria, Hamburg, America, Scandinavia, and Switzerland. Of the 6,400 square metres (68,889 sq ft) of floorspace, the model takes 1,150 m2 (12,378 sq ft)”. – Wikipedia

Photo: Details of the “Miniatur Wunderland” are pictured on April 2, 2009 in Hamburg, Germany. The world's largest model railway and one of the most popular tourist attractions in Germany is located next to the Elbe in Hamburg's Speicherstadt. (Photo by Joern Pollex/Getty Images)

Indian Air Force personnel parade during the 85th Air Force Day celebrations at Hindon Air Force base in Ghaziabad on October 8, 2017. (Photo by AFP Photo/Stringer)

A U.S. Air Force B-1B Lancer bomber sits on the runway at Anderson Air Force Base, Guam July 18, 2017. (Photo by Airman 1st Class Christopher Quail/Reuters/U.S. Air Force)

A member of the Air Force's Wings of Blue Parachute Demonstration Team salutes as he jumps out of an aircraft, during the opening ceremony of Aviation Nation 2017 Nellis Air and Space Expo at Nellis Air Force Base, Nev., November 10, 2017. (Photo by Senior Airman Kevin Tanenbaum/Reuters/U.S. Air Force)

Indian Air Force soldiers toss their rifles as they perform during the full-dress rehearsal for Indian Air Force Day at the Hindon air force station on the outskirts of New Delhi October 6, 2015. (Photo by Anindito Mukherjee/Reuters)