Behind the Façade: 40 Surprising Facts About the Hidden Secrets of Famous Landmarks

The Great Pyramid of Giza and the speed of light share an interesting numerical coincidence: the digits in the speed of light are exactly the same as the latitude of the pyramid. The Great Pyramid is located at a latitude of 29.979175°, and the speed of light is 299,792,458 m/s. The difference in latitude is 7.08E-05, or about 25 feet. With a top-down view, the central chamber is indeed around 27 feet south, and the 25-foot mark is somewhere between the antechamber and the King's Chamber.

The Arc de Triomphe contains a secret room beneath its vault that was originally intended to be a chapel but was never completed. Over the years, it has been used for a variety of different purposes.

The Alhambra palace in Granada, Spain, features stunning Islamic architecture and was built by Muslim rulers in the 13th and 14th centuries. The palace's Islamic mosaics display a near-perfect understanding of mathematical logic and 16 of the 17 types of symmetry identified by modern mathematicians, making them not just beautiful but mathematically rigorous as well. These patterns explore the fundamental characteristics of symmetry in a surprisingly complete way, and it's interesting to note that mathematicians didn't come up with their analysis of symmetry principles until centuries after the tiles of the Alhambra had been set in place.

The world-famous Neuschwanstein Castle in Bavaria, Germany, was used as a depot for the Nazis' stolen art during World War 2, with orders to blow it up that were never carried out by the SS officer in charge. Its fairytale look later inspired Walt Disney to create Cinderella's castle in the 1950 film, and the Neuschwanstein Castle became the basis for the Disney logo shown before every Disney film and the Cinderella Castle in Disneyworld, Florida.

The Forbidden City in China, built in 1420, was so well-designed that it withstood over 200 earthquakes and can withstand one with a magnitude of 10.1 on the Richter scale. During the Cultural Revolution, the Red Guards attempted to invade and destroy parts of the Forbidden City, but it was avoided when the premier Zhou Enlai sent an army battalion to guard the city. The Inner Court of the Forbidden City was the emperor’s private realm, where no other men were allowed to stay at night. Male servants who stayed overnight had both their penis and scrotum removed, and a piece of bamboo was inserted in the urethra for urination.

The Sagrada Familia is a church in Barcelona that has been under construction for over 130 years and is still not expected to be complete by 2026 at the earliest estimate. For 137 years, it was being constructed illegally and only got its building permit in 2019 when authorities found out it didn't have one in 2016. As part of his quest to create lifelike sculptures on Barcelona's Sagrada Familia, its architect, Gaudí made plaster casts of anesthetized turkeys and chickens, and even of stillborn babies.

The Palace of Versailles was originally a royal hunting lodge. In order to supply water to the parks of the Palace of Versailles, Louis XIV ordered the construction of the machine Marly to pump water from the Seine, located 10 km from the castle with a drop of 150 meters. This machine, considered one of the most complex of its time, worked for 133 years. The Moberly-Jourdain incident is an eerie incident that supposedly took place in the gardens of the Palace of Versailles in 1901. Two women claimed to have traveled back in time to the 18th century and witnessed the court of Marie Antoinette. Their story has fascinated and perplexed people ever since, with some believing it to be a genuine paranormal experience and others dismissing it as a hoax or hallucination.

The Burj Khalifa, the world's tallest skyscraper, stands on sand without any bedrock. Its base is supported by a massive concrete slab, which acts like a snowshoe and prevents it from sinking. 194 shafts of concrete were dug into ancient seashell dust to provide friction, and it is the only thing holding up the building. Despite its towering height, the Burj Khalifa is not connected to the municipal sewage system, and its waste water is transported out of town by trucks, which sometimes have to wait in line for up to 24 hours.

The Hagia Sophia, a prominent landmark in Istanbul, Turkey, was originally a Christian church before it was converted into a mosque. The city was violently conquered by the Ottomans, who murdered and raped citizens for three days with approval from their sultan. All those who held liturgies in the Hagia Sophia were killed. The mosque also sits atop an ancient series of underground tunnels, 800 feet beneath its foundation. A documentary crew, granted rare permission to explore these tunnels, discovered sealed passages, a graveyard with children's bones, and the burial chamber of the first priest of Hagia Sophia.

The Great Sphinx of Giza, one of the most recognizable landmarks in Egypt, was carved out of a single mass of limestone found in a horseshoe-shaped quarry. Some archaeologists argue that the Sphinx is far older than previously believed due to evidence of water erosion, head recarving, and megalithic sites. When confronted with these findings, the minister of Egyptology dismissed them by saying, "I don't believe in radar." The Sphinx was first restored in 1400 BC, by which time it was already several thousand years old.