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)

Labourers use a crane to lift the hand of a giant bronze statue of former King Rama I at Ratchapakdi Park in Hua Hin, Prachuap Khiri Khan province, Thailand, August 4, 2015. The park is being constructed by the Thai army to honor past Thai monarchs and is situated on an army compound near the Klai Kangwon Palace. The project is estimated to cost about 700 million baht ($20,000,000), according to local media. (Photo by Athit Perawongmetha/Reuters)

Every year National Parks Week gives visitors a chance to celebrate the incredible woodland spaces around the UK. This year the National Parks Week runs from 28 July – 3 August and there are 10 national parks across England to explore. Each one has created a special event to celebrate the National Parks Week, from picnics and treasure hunt in the park to cycle rides, safari or outdoor art exhibition. (Photo by Diana Jarvis/VisitEngland)

This Sunday, September 7, 2014 photo provided by Rachel Kirk shows smoke from a fire rising above Little Yosemite Valley near Yosemite National Park, Calif. (Photo by Rachel Kirk/AP Photo)

A large molded bust of Edward Snowden is pictured in Fort Greene Park at the Brooklyn borough of New York in this April 6, 2015 picture provided by ANIMALNewYork. A group of anonymous artists erected the 4-foot-tall bronze statue of Snowden, the former U.S. spy agency contractor famous for leaking classified information, in a New York City park overnight, officials said on Monday. (Photo by Aymann Ismail/Reuters/ANIMALNewYork)

A red deer stag watches from the cover of a bracken thicket during the autumn rutting season at Richmond Park on October 10, 2011 in London, England. Autumn sees the start of the “Rutting” season where the stags and bucks bellow in an attempt to attract female does and hinds. (Photo by Dan Istitene/Getty Images)

Five-year-old Julian Becker and his 165 pound pet Newfoundland Max have been best buds around all their lives. To commemorate the friendship and to keep Julian's father, a Naval officer who is often away, in the loop, Julian's mom Stasha began taking photos. Photo: Hats off (or on) to Julian for sharing his blanket with his good buddy. Not that the furry beast needs it... (Photo by Stasha Becker/Rex Features)