“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)

A man works on a small replica of the Iron Man armor next to a homemade replica of the “Hulkbuster” Iron Man armour from the movie “Avengers: Age of Ultron”, at an underground parking lot in Zhengzhou, Henan province, China, May 12, 2015. The 3.4-metre-tall replica is made of over 100 fiber-reinforced plastic components. It took Xing and his friends two months to put them together after watching the trailer of the movie in March, local media reported. (Photo by Reuters/Stringer)

Crowds look on as the super moon rises behind the Fremantle War Memorial at Monument Hill on November 14, 2016 in Fremantle, Australia. A super moon occurs when a full moon passes closes to earth than usual, with the November 14th moon expected to be closer than it has been in over 70 years. (Photo by Paul Kane/Getty Images)

Wounded Reuters photographer Gleb Garanich, who was injured by riot police, takes pictures as riot police block protesters during a scuffle at a demonstration in support of EU integration at Independence Square in Kiev November 30, 2013. Riot police in the Ukrainian capital Kiev used batons and stun grenades to disperse hundreds of pro-Europe protesters from the city's main Independence Square early on Saturday, witnesses said. (Photo by Reuters/Stringer)

A firefighter holds a red panda (Ailurus fulgens) from its tail while removing it from a tree at a residential area in Kunming, Yunnan province, July 3, 2014. The animal was spotted in the residential area and was brought down from the tree after residents reported its sighting to the police, local media reported. (Photo by Reuters/Stringer)

A police officer wearing a protective mask walks past the portrait of late communist leader Mao Zedong (not pictured) at Tiananmen Gate in Beijing on January 23, 2020. Large-scale Lunar New Year events in Beijing have been cancelled as part of national efforts to control the spread of a new SARS-like virus, city authorities announced on January 23. (Photo by Nicolas Asfouri/AFP Photo)

A person wearing a mask of Elmo walks around Times Square during the pass of the snowstorm on January 31, 2021 in New York City. New York City Mayor Bill de Blasio declared a state of emergency order due to the arriving storm that's expected to wallop New York, where airports are expected to cancel the majority if their flights. (Photo by Eduardo Munoz Alvarez/VIEWpress)

Dog Xiaoniu dressed in clothes walks across a street with its owner (not pictured) in Shanghai, December 19, 2014. According to local media, Xiaoniu accompanies its owner to the food market everyday and is able to walk with its hind legs for up to about an hour. (Photo by Reuters/Stringer)