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Siena Cathedral, Siena, Italy -

Siena's majestic cathedral is missing the proposed extension of its nave. Construction halted in 1348 when the Black Death swept across Europe. In fact, several unfinished walls are still standing, as work was never resumed.

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Metropolitan Museum of Art, New York City, USA -

One of the world's most celebrated museums appears complete, but look closely at the top of the columns. They are capped with pyramids of rough limestone. Originally earmarked for carved ornamentation, these sculptures were never realized due to the financial Panic of 1901.

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Centro Financiero Confinanzas, Caracas, Venezuela -

Also known as Torre de David in honor of the project's main investor, the now deceased David Brillembourg, Centro Financiero Confinanzas is an abandoned skyscraper set in the capital of Venezuela. It stands empty as a victim of the country's banking crisis of 1994, although some floors were occupied by squatters in the early 2000s.

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National Monument of Scotland, Edinburgh, Scotland -

Conceived as a memorial to the Scottish soldiers and sailors who died fighting in the Napoleonic Wars, the National Monument of Scotland stands unfinished over Edinburgh due to lack of funds, which ran dry in 1829.

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Alai Minar, Delhi, India -

Set near the famous Qutub Minar of Delhi is the lesser-known circular monument known as Alai Minar. An unfinished tower that was started by Alauddin Khalji of the Khalji dynasty in 1311 CE, the massive structure was abandoned after his death. It is the only unfinished monument in the Indian capital.

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Rashid Karameh International Exhibition Center, Tripoli, Lebanon -

Designed by no less than famed Brazilian architect Oscar Niemeyer, the Rashid Karameh International Exhibition Center in the northern Lebanese city of Tripoli was conceived as a national pavilion. Construction started in 1964 and was still ongoing when the outbreak of civil war in 1975 forced the project's closure. In 2018, the building was nominated for the World Heritage Tentative list by UNESCO.

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Germania, Berlin, Germany -

The idea of Germania was Hitler's renewal of Berlin, a megacity he envisaged as a world capital after the Nazi's planned victory in the Second World War. Albert Speer, Hitler's architect, was tasked with drawing up the blueprints, but only a small portion of the project was realized between 1938 and 1943. Ultimately the war and defeat buried the plans.

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Strasbourg Cathedral, Strasbourg, France -

The magnificent Strasbourg Cathedral stands as one of the finest examples of French Gothic architecture. This despite the fact that this prominent place of worship, completed in the 15th century, is missing its southern tower. It was never built after the ecclesiastical coffers ran dry.

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Herrenchiemsee, Chiemsee, Germany -

A much-visited tourist attraction, Neues Schloss on Herreninsel, the largest island in Chiemsee lake in southern Bavaria, was commissioned by King Ludwig II in 1878. From the outside, the palace appears grand enough. But after the king's death in 1886, there was no money left to complete the interior. Just 20 of the proposed 70 rooms were built.

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Prora, Rügen, Germany -

Building work on Prora, a planned holiday resort for German workers located on the island of Rügen, began in 1936. But by 1939 the complex still hadn't been completed. During the Second World War, it was used by the Nazis as a training base and later by Soviet military authorities for the same purpose. Today partially restored, Prora serves as a youth hostel and a vacation aparthotel.

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Boldt Castle, Heart Island, USA -

Heart Island in the Thousand Islands region of New York state is where you'll find Boldt Castle. Part-built as a private mansion for American millionaire George Boldt, construction stopped in 1904 after the death of his wife. The castle remained abandoned for 73 years until local authorities financed a restoration project, which has seen many of the rooms refurbished. Others have been left empty on purpose to give the visitor an opportunity to imagine what the castle looked like before its recovery.

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Woodchester Mansion, Gloucestershire, England -

A Grade I listed building in England, Woodchester Mansion is a late 19th-century shell. Inside, whole floors are missing, as well as rooms⁠—all too expensive to complete. The one finished room, the drawing room, is open to visitors, while the only permanent residents are a colony of greater horseshoe bats.

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Neuschwanstein Castle, Hohenschwangau, Germany - Picture-book Neuschwanstein Castle in Bavaria was another architectural project commissioned by King Ludwig II, and another ambitious property that was never fully completed. Lack of funds and resources meant numerous rooms were left unbuilt, including what would have been the opulent Moorish Hall.

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Kellie's Castle, Batu Gajah, Malaysia -

Named for Scottish civil engineer William Kellie-Smith, Kellie's Castle is located in Batu Gajah, Malaysia. Kellie-Smith commissioned the property in 1915, likely as gift for a family member. Misfortune struck, however, when he died of pneumonia in 1926. With no money to pay the workforce, his widow moved back to Scotland and construction on the castle was never completed. It's now a popular tourist site.

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National Art Schools, Havana, Cuba -

Cuba's National Art Schools in Havana were conceived and founded by Fidel Castro and Che Guevara in 1961. Five were originally planned, but only two were ever completed. The remaining three were largely abandoned and stood in near-ruin for years. Eventually the trio of uncompleted buildings were restored, and the entire facility is now included on the World Monuments Watch list.

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Marble Hill Nuclear Power Plant, Hanover, USA -

A nuclear power plant is hardly something you'd expect to be abandoned, but in 1984 that's exactly what happened when work on the half-completed Marble Hill Nuclear Power Plant near Hanover in Indiana was halted. Nearly US$3 billion had already been spent when the decision was made to close the facility—one of many such cancellations ordered in the wake of the Three Mile Island nuclear accident in Pennsylvania in 1979. Marble Hill is presently undergoing demolition.

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Watkin's Tower, London, England -

Designed to compete with the Eiffel Tower in France, Watkin's Tower was a partially completed iron lattice tower in Wembley Park that was demolished in 1907 after construction costs spiraled out of control.

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Basilica of San Petronio, Bologna, Italy -

Bologna's imposing Basilica of San Petronio is noted for its unfinished facade, which was started in 1538 but later abandoned by architect Giacomo Ranuzzi for reasons that still remain unclear.

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Sathorn Unique Tower, Bangkok, Thailand -

The 1997 Asian financial crisis spelt the end for the Sathorn Unique Tower, even though by then it was 80% complete. It now stands as one of Bangkok's most prominent derelict buildings.

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Abbey of Santissima Trinità, Venosa, Italy -

Italy's Abbey of Santissima Trinità in Venosa includes a "new" church building started in the 11th century and never completed. The monastery itself remains, but today is used by the Trinitarians, a Catholic religious order founded in the 12th century.

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Jeddah Tower, Jeddah, Saudi Arabia -

Begun in 2013 and still incomplete, the Jeddah Tower, also referred to as the Kingdom Tower, has languished for 10 years in construction limbo. It was planned as the world's first 1-km (3,281-ft) tall building.

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Pyramid of Neferefre, Abusir, Egypt -

Unlike those found at the world-famous Giza complex, the Pyramid of Neferefre was never finished. It was started in the 25th century BCE for the Egyptian pharaoh Neferefre, but owing to the unexpectedly early death of the pharaoh it was abandoned. The adjoining mortuary temple was completed, but many years after Neferefre's passing.

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Palace of the Soviets, Moscow, Russia -

Designed in the early 1930s at the height of Stalin's rule, the ambitious Palace of the Soviets would have stood as a political convention center in the middle of Moscow. Building work was interrupted by the outbreak of the Second World War, after which the project was scrapped. If completed, the 416-m (1,365-ft) tall building would have become the world's tallest structure.

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Chicago Spire, Chicago, USA -

The only evidence of the much-lauded Chicago Spire building project is the base excavation and construction site, dormant since 2008. Had it gone ahead, the skyscraper would have stood 610 m (2,000 ft) high with 150 floors and would have been the tallest building in the Western Hemisphere.

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Palacio Legislativo Federal, Mexico City, Mexico -

Mexico City's ambitious Palacio Legislativo Federal should have ended up looking like this. Instead, only the foundations and the iron structure were completed, and even these were eventually destroyed. But out of the ashes rose the city's Monumento a la Revolución, the cupola having been saved and now seen crowning the landmark commemorating the Mexican Revolution.

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Cathedral of St. John the Divine, New York City, USA -

Though consecrated in 1911, the Big Apple's Cathedral of St. John the Divine is only two-thirds complete. Labor disputes, uneven foundations, and stylistic changes all contributed to delays and funding shortfalls until it was decided to cut losses and unveil what is still today one of the largest churches by area in the world.

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Sagrada Família, Barcelona, Spain -

Construction on Sagrada Família began in 1882. Designed by the Catalan architect Antoni Gaudí, this famous Barcelona landmark is the largest unfinished Catholic church in the world. It's anticipated that all its decorative elements should finally be in place by 2026, more than 140 years after groundbreaking.

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Hassan Tower, Rabat, Morocco -

Hassan Tower stands as the minaret of an incomplete mosque that would have served the population of Rabat, in Morocco. Commissioned by Abu Yusuf Yaqub al-Mansur, the third Caliph of the Almohad Caliphate, the mosque was abandoned in 1199 after al-Mansur's death, leaving only the tower as testament to what might have been.

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Ryugyong Hotel, Pyongyang, North Korea -

Construction began in 1987 on the Ryugyong Hotel, an enormous pyramid-shaped skyscraper set in the North Korean capital. But the economic crisis that befell the country after the dissolution of the Soviet Union in 1991 stalled construction. To date the building remains unfinished and has been dubbed outside of North Korea as the "Hotel of Doom."

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Beaumaris Castle, Anglesey, Wales -

From the air, Beaumaris Castle on the Welsh island of Anglesey appears as a 14th-century ruin should. But in fact it looks as it does because it was never completed, with work ceasing after Edward I's invasion of Scotland effectively diverted funding from the project.

See also: The most beautiful castles in Europe

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