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Israel -

Israel's building rules, changed in 1951, require every new home or business to have a safe room, often called a 'Mamad' (short for "residential secure space").

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Nahariya, Israel -

These rooms are made to stay strong during rocket strikes or attacks involving harmful substances. They have become a regular part of how buildings are designed in Israel.

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Kashan, Iran -

To the north of Kashan lies Ouyi, a 1,500-year-old marvel of Sassanian architecture and engineering. This underground city was created as a refuge for residents to seek shelter from unwanted intruders. Certain sections of the tunnels and chambers are accessible for public viewing.

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Derinkuyu, Turkey -

Constructed in the Byzantine period, Derinkuyu's remarkable underground city housed a substantial population of 20,000 and served as an impressive fortress against enemy assaults. Today, most parts of this historic complex can be explored by tourists.

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New York City, USA -

The oldest building in New York's Central Park is Blockhouse No 1, which dates back to the early 19th century and the War of 1812. It is a two-story bunker that serves as a significant piece of history within the park.

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Gibraltar, UK -

Since the late 18th century, an impressive 34 miles (55 km) of tunnels have been excavated in the Rock of Gibraltar. These tunnels have served various purposes, including hospitals, barracks, and ammunition storage. While most have been decommissioned, a few are accessible to the public.

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Alderney, UK -

"The Odeon," a bunker known locally as a noteworthy fortification, stands out among the many built by German forces during their occupation of the Channel Islands.

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Pointe du Hoc, France -

During WWII, the promontory in Normandy held immense strategic value as it served as the prominent point between Utah Beach in the west and Omaha Beach in the east. Concrete bunkers and casemates are scattered along the coastal area.

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Colmenar del Arroyo, Spain -

This characteristic bunker installation was built by Nationalist forces during the Spanish Civil War.

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Cabinet War Rooms, London -

The secret bunker in Westminster, one of the UK's top visitor attractions, has been carefully maintained to retain its original condition.

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Skanderborg Forest, Denmark -

The remains of the German Luftwaffe headquarters during WWII in Denmark consist of four bunkers, two of which have been transformed into museum displays.

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Cap d'Antifer, France -

Bunkers along the Normandy coast are reminders of the Atlantic Wall, the Nazis' defensive fortifications.

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Landrethun-le-Nord, France -

Located beneath a serene area in rural France, the extensive bunker complex, known as Forteresse de Mimoyecques, was intended to shelter the Nazis' lethal V3 rocket. Luckily, this devastating weapon was unsuccessful in its launch.

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Cape May Point, USA -

The abandoned WWII bunker is a notable local landmark due to its unconventional location on a New Jersey beach.

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Jersey, Channel Islands -

The only British territory to be occupied by the German Army during WWII, the island group includes Jersey, the location of the Jersey War Tunnels. The tunnels were designed to withstand Allied air raids and bombardments.

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Liepāja, Latvia -

The underground tunnels and bunkers of the Northern Forts, dating back to Tzarist Russia, make up a remarkable fortress.

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Moscow, Russia -

Bunker 42, a hidden Soviet bunker from the 1950s found beneath Moscow, functions as the Cold War Museum as well.

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Līgatne, Latvia -

The underground nuclear shelter in rural Līgatne, built for the Communist elite during the Cold War, stayed hidden for 30 years.

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Konjic, Bosnia and Herzegovina -

In 1953, Yugoslav communist revolutionary and political leader Josep Broz Tito (1892–1980) ordered the construction of a nuclear bunker inside a mountain. Today it's a funky modern art exhibition space. 

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Elbasan, Albania -

Similarly, under the autocratic regime of Enver Hoxha (1908-1985), the Communist dictator commanded the construction of numerous bunkers that now lay in dilapidated abandonment throughout the nation.

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York, England -

The York Cold War Bunker, operational from the early 1960s until the mid-'90s, served as a monitoring center for fallout during nuclear strikes. Today, it remains an intriguing tourist destination.

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Moscow, Russia -

Stalin's Bunker, which traces its origins to World War II, served as the strategic planning hub for the Russian dictator during some of history's most gruesome battles, all while evoking a chilling atmosphere.

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Budapest, Hungary -

Located beneath Buda Castle Hill, Hospital in the Rock was originally used as a hospital during WWII. It was later transformed into a nuclear shelter during the Cold War era. Visitors can learn more about its fascinating history at the museum.

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Cheshire, England -

The Hack Green Secret Nuclear Bunker, a former government-owned underground command center, is a Cold War secret that has recently been revealed to the public after 50 years.

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Fife, Scotland -

Scotland's Secret Bunker, situated beneath an unassuming farmhouse, spans an area equivalent to two soccer fields and has become a highly captivating tourist destination in the area.

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Kelvedon Hatch, UK -

Brentwood, a peaceful borough, had been hiding a massive and secret Cold War bunker for many years. Taking a tour allows one to explore this intriguing facility and gain insight into its covert history.

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Ho Chi Minh City, Vietnam -

Veterans from all parties of the war unite with curious visitors to explore the Củ Chi tunnels, an extensive system of passages and shelters that presently constitute a memorial park for the Vietnam War in the city.

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Quang Tri, Vietnam -

Visitors can also explore the Vịnh Mốc tunnels by joining a guided tour.

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Berlin, Germany -

During the final weeks of WWII, Hitler sought refuge in his notorious bunker complex, which has become a symbol of infamy in history. The photo shows a US serviceman in what is believed to be the Führer's study, the very room where it is believed that the defeated German dictator and his wife Eva Braun met their end. 

See more: The Israel-Hamas conflict: It started way before you think

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