Željava Air Base, situated on the border between Croatia and Bosnia and Herzegovina under Plješevica Mountain, near the city of Bihać, Bosnia, was the largest underground airport and military air base in the former Yugoslavia, and one of the largest in Europe. (Photo by Thomas Windisch/Exclusivepix Media)

A UCLA student is arrested by Los Angeles Police Department officers after she attempted to escape after eleven student protesters sat in circle in middle of the Westwood and Wilshire boulevard intersection as part of a protest of bank practices and rising fees at public universities on November 9, 2011 in Los Angeles, California. The protest organized by ReFund California was one of several planned at universities around the state. (Photo by Kevork Djansezian/Getty Images)

Bex Hetherington exhibits a T-shirt at the Edinburgh College of Art degree show on June 8, 2011 in Edinburgh, Scotland. Students work will be exhibited across the campus buildings turning Edinburgh College of Art into the city's biggest gallery space. The work ranges from conceptual to commercial with inspirational influences as diverse and wide ranging as fashion photography, volcanoes, the crazy lady who put a cat in a bin, fairytales, the star system and serial killers. (Photo by Jeff J Mitchell/Getty Images)

A burning train wagon is seen after an explosion at Lac Megantic, Quebec, July 6, 2013. A large swath of Lac Megantic was destroyed Saturday after a train carrying crude oil derailed, sparking several explosions and forcing the evacuation of up to 1,000 people. (Photo by Mathieu Belanger/Reuters)

This awesome book sculpture is by Thomas Wightman and is the most recent of the series, if you would like to see his two previous sculptures do so via his website.

This summer China opened its door to its first private bodyguard training company in Beijing. Genghis Security Academy offers rigorous training course which includes aquatic training, martial arts, vehicle safety training and other necessary skills. Photo: Female and male trainees run during a bodyguard training program at the boot camp of Genghis Security Academy in Beijing, China. (Photo by ImagineChina/The Grosby Group)

A performer dressed as a Hello Kitty poses inside a Hello Kitty-themed Taroko Express train in Taipei, Taiwan March 21, 2016. Lucky fans of Hello Kitty were among the first to ride a train themed after the iconic fictional character on its inaugural run in Taiwan on Monday. The Hello Kitty-themed Taroko Express train, the first in Taiwan, set off from the Shulin train station and will travel to Taitung on the east coast route. The Taiwan Railway Administration, which will introduce Hello Kitty merchandise, said it plans to adds more themed trains to its fleet. (Photo by Tyrone Siu/Reuters)

Number 10. BELL H-13 SIOUX was a two-bladed, single engine, light helicopter built by Bell Helicopter. Westland Aircraft manufactured the Sioux under license for the British military as the Sioux AH.1 and HT. In 1947, the United States Air Force ordered the improved Bell Model 47A. Most were designated YR-13 and three winterized versions were designated YR-13A. The United States Army first ordered Bell 47s in 1948 under the designation H-13. These would later receive the name Sioux. The Bell-built H-13 B is seen airborne in this April 29, 1951 photo. The helicopter is equipped with a 173 horsepower engine, cruises at 85 miles per hour, climbs 900 feet in a minute and has a service ceiling of 11,500 feet. (Photo by AP Photo)