Free runners “3run” take advantage of O2's empty Slough HQ on the company's flexible working day on February 8, 2012 in Slough, England. (Photo by Ian Gavan/Getty Images for O2)

Model Jennifer Hawkins showcases designs by Yeojin Bae on the catwalk at the Myer A/W 2012 Collection Launch on March 1, 2012 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images)

Artist Richard Neave admires the sculpture “Sprinting” that he created with Denise Smith on March 12, 2012 in London, England. The model shows the body of elite athlete, Richard Whitehead, and forms the centre piece at the Anatomy Of An Athlete Exhibition opening at the Hunterian Museum. (Photo by Bethany Clarke/Getty Images)

Soyuz VS01 is lifts off at the European Spaceport on October 21, 2011 in Kourou, French Guiana. The Soyuz VS01 rocket is carrying the first two satellites of Europe's Galileo navigation satellite system into orbit. (Photo by Stephane Corvaja/ESA via Getty Images)

Sports Illustrated Swimsuit model Alyssa Miller attends SI Swimsuit Launch Party Hosted by Crimson at Crimson on February 14, 2012 in New York City. (Photo by Michael Loccisano/Getty Images for Sports Illustrated)

A plume of smoke rises above Gaza City as Israeli air strikes hit on August 18, 2011 in Gaza City, Gaza. The airstrikes came hours after attacks by militants killing Israelis in a cross border operation near Eilat, Southern Israel. (Photo by Christopher Furlong/Getty Images)

Adele Clark, aged 8, looks at an animatronic Gallimimus dinosaur at the Natural History Museum on April 20, 2011 in London, England. The Age of the Dinosaur is a summer exhibition combining animatronic models, fossils and CGI film footage. (Photo by Matthew Lloyd/Getty Images)

“Dover Castle is a medieval castle in the town of the same name in the English county of Kent. It was founded in the 12th century and has been described as the “Key to England” due to its defensive significance throughout history. It is the largest castle in England.

The outbreak of the Second World War in 1939 saw the tunnels converted first into an air-raid shelter and then later into a military command centre and underground hospital. In May 1940, Admiral Sir Bertram Ramsey directed the evacuation of French and British soldiers from Dunkirk, code-named Operation Dynamo, from his headquarters in the cliff tunnels”. – Wikipedia

Photo: The Repeater Station in the subterranean tunnels underneath Dover Castle, which has been restored by English Heritage for a public exhibition on June 3, 2011 in Dover, England. The evacuation of allied soldiers from Dunkirk was masterminded and co-ordinated from the secret command and control centre in the tunnels deep below the castle. (Photo by Matthew Lloyd/Getty Images)