“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)

Beryl Lipton, left, douses Matt Lee during the ice bucket challenge at Boston's Copley Square, Thursday, August 7, 2014 to raise funds and awareness for ALS. The idea is: pay up for charity or get doused. The fund-raising phenomenon is catching on fast, propelled by popular videos of the dunkers and the dunked – including famous athletes and entertainers – posted on social media sites. And the challenges are raising tens of thousands of dollars and immeasurable awareness for causes from ALS to breast cancer to a camp for kids who've lost a father to war. (Photo by Elise Amendola/AP Photo)

Members of the U.S. Army 173rd Airborne Brigade stand at attention as a Ukrainian folk dance group performs at the opening ceremony of the “Rapid Trident” NATO military exercises on September 15, 2014 near Yavorov, Ukraine. The two-week exercises include participating units from a variety of NATO and NATO-associate countries as well as Ukrainian troops. Meanwhile fighting between pro-Russian separatists and Ukrainian armed foces has flared again in eastern Ukraine in a battle for the control of Donetsk airport despite the tenuous ceasefire. (Photo by Sean Gallup/Getty Images)

A model walks off stage in the backstage area during Frankie's Bikinis show at Mercedes Benz Swim Fashion Week in Miami, July 18, 2014. (Photo by Carlo Allegri/Reuters)

The 100-metre (300-foot), sword-wielding statue of “The Motherland” is seen in the National Museum of the History of the Great Patriotic War in Kiev March 17, 2014. On a blustery day on the banks of the Dnieper, the statue of “The Motherland”, a Soviet hammer and sickle on her shield, towered overhead, a reminder of the common cause Ukrainians and Russians died for side by side in their millions in World War Two and which Russian President Vladimir Putin thinks Ukraine has betrayed by turning to “fascism” and the West. (Photo by Konstantin Grishin/Reuters)

Military school cadets take part in a ceremony commemorating the 56th anniversary of the death of Camilo Cienfuegos who, along with Fidel Castro and Che Guevara, was a chief commander of the Cuban revolution in Havana, Cuba on October 28, 2015. (Photo by Xinhua/REX Shutterstock)

An Indonesian man displays his collection of rings with various gemstones at an exhibition and competition of the best gemstone at a mall in Jakarta on August 6, 2015. The recent fad of collecting rings with precious gemstone or polished gemstone locally called “batu akik” is sweeping across Indonesia, with collectors going for the very rare stones and it's possession many believe will give the owner supernatural power. (Photo by Bay Ismoyo/AFP Photo)

In this September 16, 2017 photo, a music fan poses for the photo against an angel wings' mural at the Rock in Rio music festival in Rio de Janeiro, Brazil. (Photo by Leo Correa/AP Photo)