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Plymouth, Montserrat -

Once the thriving capital of the Caribbean island of Montserrat, Plymouth was buried by debris and volcanic ash after the explosive eruption of the Soufrière Hills volcano in 1997. A modern-day Pompeii, what's left of the city has become a destination for the morbidly curious.

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Somme Battlefields, France -

Undulating earth marking the outline of trenches serves as a permanent reminder of how real World War I was for the many millions caught up in the conflict.

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Sedlec Ossuary, Czech Republic -

Located just outside the town of Kutna Hora is a small medieval chapel. Venture inside and you're greeted by more than 40,000 human bones decorating the interior.

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Auschwitz Concentration Camp, Poland -

This is the largest mass murder site in human history. An estimated 1.1 million people died here (the majority Jewish), more than at any other Nazi concentration camp. Visiting Auschwitz is an especially moving and deeply emotional experience.

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Tuol Sleng Genocide Museum, Cambodia - A high school building in Phnom Penh was appropriated by Pol Pot's Khmer Rouge security forces and turned into a prison known as Security Prison 21. An estimated 20,000 people were imprisoned here. Only 12 are known to have survived.

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National September 11 Memorial & Museum, USA - New York City has honored the 2,977 victims of the September 11, 2001 terrorist attacks with a remarkable installation consisting of a pair of granite pools marking the footprints of the two towers. An adjacent museum houses a collection of artifacts, images, oral recordings, and videos from that fateful day.

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Kigali Genocide Memorial, Rwanda -

The final resting place for 250,000 victims of the genocide against the Tutsi, the center also honors the more than one million estimated to have died in the 1994 conflict.

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Oradour-sur-Glane, France -

One of the most poignant reminders of the numerous atrocities carried out by the Nazis during World War II, this ruined village has been left as a memorial to the 642 inhabitants who were murdered on June 10, 1944, in a reprisal attack carried out by an SS Panzer Division.

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Pompeii, Italy -

The ancient Roman city was buried under 4 to 6 m (13 to 20 ft) of volcanic ash and pumice in the catastrophic eruption of Mount Vesuvius in 79 BCE. Plaster casts of victims lie on site among the extensive ruins.

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Glencoe Massacre, Scotland -

Even in summer, a mildly disturbing air permeates around this Scottish Highlands landmark. The fact is that on February 13, 1692, around 38 men from the Clan McDonald were cut down by government forces in what was later dubbed the Glencoe Massacre. In winter, this is a dark and brooding destination.

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Hiroshima Peace Memorial, Japan - Linger here after dark when the crowds have dispersed and the full horror of that horrific August 6 day in 1945 slowly but inexorably sinks in.

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Aokigahara, Japan -

Eloquently described as the "Sea of Trees" due to its verdant canopy, Aokigahara forest, resting in the foothills of Mount Fuji, is known more darkly as the world's second-most popular destination for those wanting to end their lives. Warning! If you visit here you're very likely to come across someone who has taken their own life, such is the destination's grim reputation.

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Yingxiu Township Memorial Sculpture, China - On May 12, 2008, a deadly earthquake shook Yingxiu Township to pieces. In all, around 90,000 people in Sichuan Province lost their lives. A large granite clock erected in front of a collapsed school reads 2:28 pm, the time the first tremors struck.

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Karosta Prison, Latvia -

Located in Liepaja on the Baltic Sea coast, Karosta was used as a Nazi and Soviet military prison, where torture and execution were commonplace. Decommissioned in 1994, the prison is now a museum, and visitors can spend a night in the guardhouse as an "inmate."

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The Ridges Cemetery, USA -

Dating back to the late 19th century, this cemetery in Athens, Ohio, is the final resting place of deceased patients from the Athens Lunatic Asylum. The mental hospital was notorious for carrying out questionable lobotomy procedures, and for several alleged paranormal sightings said to have taken place in and around the premises.

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Capela dos Ossos, Portugal -

This macabre former place of worship in the city of Évora is lined with the broken skeletons of around 5,000 monks. The warning above the entrance reads in translation: "We bones that are here, await yours."

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Dachau Concentration Camp, Germany -

Dachau, set on the outskirts of Munich, was the first of the Nazi concentration camps to open in Germany, this in 1933. By the time it was liberated on April 29, 1945, the majority of the camp's prisoners were classified as political prisoners (and most of them were Catholic).

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Island of Dolls, Mexico -

Dozens of creepy toy dolls adorn the trees on this island in the Xochimico canal system, south of Mexico City. It's said that the dolls, placed by locals, are possessed by the benign spirits of a number of girls who drowned in the canal waters.

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Belchite, Spain -

The Battle of Belchite, in Aragon, took place in August and September 1937 during the Spanish Civil War. The town was completely destroyed, but Francisco Franco ordered that the ruins be left untouched. The empty shells of once handsome buildings stand as testimony to the savagery of the fighting.

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Panorama Museum of the Battle of Stalingrad, Russia -

Nearly two million combatants were killed, wounded, or captured during the apocalyptic Battle of Stalingrad. Renamed Volgograd, the city honors the largest confrontation in World War II with this museum, which stands next to the eerie ruins of an old mill, one of the few buildings that survived the onslaught. 

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Poenari Castle, Romania -

Vlad the Impaler, the barbaric 15th-century warlord who inspired Bram Stoker's Dracula, ordered the repair and strengthening of this remote citadel, perched high up on the plateau of Mount Cetatea.

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Memorial Hall of the Victims in Nanjing Massacre by Japanese Invaders, China - Nanjing, the then-capital of China, fell to Japanese forces on December 13, 1937. In six weeks, an estimated 300,000 inhabitants were massacred. The museum memorializes those who were killed.

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Echo Valley, Philippines -

Glance upwards when you hit the trails in the mountain province of Sagada. Suspended from cliff faces in Echo Valley are dozens of suspended coffins. Some are centuries old while others date back just a few years. They are all occupied.

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Agdam, Azerbaijan -

During the 1993 war in the disputed region of Nagorno-Karabakh, the town of Agdam was captured by Armenian forces and the residents were forced to flee. It's been abandoned ever since. It's illegal to enter, but intrepid travelers have found ways to bypass the authorities and catch a glimpse of this near ruined destination.

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Babi Yar, Ukraine - A name synonymous with the unspeakable horrors perpetrated by the Nazis during World War II, Babi Yar, a ravine near the capital Kiev, was the scene of massacres carried out by German forces at the end of September 1941 and in January and February, 1942.

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Perm 36 Gulag, Russia -

Hidden away in the forest of Western Siberia is this former Soviet forced labor camp. This is the only proper memorial site and museum at an authentic gulag prison.

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Son My Memorial, Vietnam -

One of the Vietnam War's darkest episodes took place on March 16, 1968, when US troops killed up to 500 South Vietnamese civilians in what became known as the My Lai Massacre. A memorial stands in the nearby hamlet of Tịnh Khe.

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Paris Catacombs, France -

Deep under the French capital is a network of tunnels lined to the ceiling with skulls and bones. These catacomb ossuaries mark the final resting place of around six million Parisians, originally moved from overcrowded cemeteries in the 18th century.

See also: Creepy abandoned malls around the world

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