The research and development carried out in Peenemünde was not only crucial to the course of WWII, but impacted the future of weapons of mass destruction, as well as space travel.

The Borovsko Bridge is an unfinished highway bridge near Borovsko , part of Bernartice municipality, Central Bohemian Region, Czech Republic. It is commonly known as the "Czech Avignon" or "Hitler's Bridge".

Situated in the west of Bosnia on the border with Croatia, Objekat 505, as it was officially known, was the largest underground airport in the Balkans. The primary purpose of the Objekat 505 was to house a long-range radar early warning system, akin to NORAD, as well as to provide a strategic command center for the country’s defense.

Prora, also known as the Colossus of Prora, is an enormous building complex on the island of Rügen, Germany, that was built by Nazi Germany between 1936 and 1939 as a beach resort of the Strength Through Joy (Kraft durch Freude or KdF) project.

The Vajont Dam (or Vaiont Dam) is a disused dam in Italy, which was completed in 1959. On 9 October 1963, during initial filling, a massive landslide caused a man-made megatsunami in the lake in which 50 million cubic metres of water overtopped the dam in a wave 250 metres (820 ft) high, leading to 1,910 deaths and the complete destruction of several villages and towns.

Germany’s “treasure chamber” is located in a disused mine near Freiburg. Documents from over a thousand years of history are stored in the underground archive.

Bagger 288 (Excavator 288), built by the German company Krupp for the energy and mining firm Rheinbraun, is a bucket-wheel excavator or mobile strip mining machine.

The Stelling van Amsterdam was the most advanced military structure of its type in the world - 135 km (84 miles) of forts, batteries and moats completely encircling the city in a defensive barrier.

The National Monument of Scotland, on Calton Hill in Edinburgh, is Scotland's national memorial to the Scottish soldiers and sailors who died fighting in the Napoleonic Wars.

The Post Office Railway, known as Mail Rail since 1987, is a driverless underground railway that was built to move mail between sorting offices.

SS Richard Montgomery was an American Liberty ship built during World War II, one of the 2,710 used to carry cargo during the war.

The Outer Trial Bank is a circular artificial island in the Wash, East Anglia, England. It is one of two islands constructed during the 1970s for a governmental water resources scheme.

Kupari was once a hugely popular holiday resort, until it was damaged during the Croatian War of Independence.

The Cultybraggan camp is one of the last remaining World War 2 Prisoner of War Camp in the UK.

Some 250 million years ago, a part of Ukraine was under a shallow ocean. When the ocean dried up, it left behind a huge deposit of salt.

Riese is the code name for a construction project of Nazi Germany in 1943–1945, consisting of seven underground structures located in the Owl Mountains and Ksiaz Castle.

Checkpoint Charlie was the name given by the Western Allies to the best-known Berlin Wall crossing point between East Berlin and West Berlin during the Cold War.

The Berlin Wall was a guarded concrete barrier that physically and ideologically divided Berlin from 1961 to 1989.

The Kelvedon Hatch Secret Nuclear Bunker at Kelvedon Hatch, in the Borough of Brentwood in the English county of Essex, is a large underground bunker maintained during the cold war as a potential regional government headquarters.

In 1959 it was the centre of project Military Atomic Energy Authority operation orpheus investigating the possibility of masking the seismic signal given out by underground nuclear tests.

In the early l950s, RAF Barnham was selected for development as a dedicated storage and maintenance facility for nuclear weapons, in particular for Blue Danube, Britain's first nuclear bomb.

Danish artist Thomas Dambo has been building stuff using trash and recycled materials since an early age, starting with smaller sculptures such as birdhouses and furniture to bigger pieces such as the six “Forgotten Giants” he recently installed around Copenhagen.

Five meters below the runway of Sarajevo's airport runs a short stretch of tunnel that was dug out during the Siege of Sarajevo to bring supplies to the cut-off city. For four years this 800-meter long tunnel was the besieged city’s only connection to the outside world, and its life support.

About twenty kilometers from the city of Boulogne-sur-Mer, near the hamlet of Mimoyecques, in northern France, lies a once-secret underground Nazi base.

Vilarinho da Furna, in the municipality of Terras de Bouro in the Braga district, in northern Portugal, was an old village that was erased from the map in 1972.

Equihen Plage, on the coast of northern France by the English Channel, is a small seaside village with a population of about 3,000.

About 25 miles south of Berlin lies the small town of Wunsdorf, home to about six thousand inhabitants. But less than thirty years ago it had a population of sixty thousand, of which fifty thousand were soldiers of the Red Army. They lived inside one of the biggest military bases in Europe and the biggest […]

The haunting buildings of the Vallone dei Mullini, or Valley of the Mill, in Sorrento, Italy were only abandoned in the 20th century, according to Atlas Obscura.

In a small neighborhood known as Monceau-sur-Sambre, within the Belgian town of Charleroi, sits an abandoned power station, the magnificent abandoned cooling tower of which still looms over the town no longer creating electricity, but providing plenty of dystopian vistas.

Preikestolen or Prekestolen (English: Preacher’s Pulpit or Pulpit Rock) is a famous tourist attraction in the municipality of Forsand in Rogaland county, Norway. Preikestolen is a steep cliff which rises 604 metres (1,982 ft) above the Lysefjorden. Atop the cliff, there is an almost flat top of approximately 25 by 25 metres (82 ft × […]