Secret Facts About The World’s Most Iconic Buildings

Great Pyramid Secret: Khufu’s Pyramid in Giza Was Not the First!

For all of the Great Pyramid’s fame, the Great Pyramid was not the first Pyramid. Sneferu, Khufu’s father, tried to build several. One of his earliest attempts was the Collapsed Pyramid at Meidum (c. 2600 BCE). Engineers tried to smooth the sides by filling in the ‘steps’ of a stepped pyramid with stone. It didn’t work. The fill sits in a rubble heap at the base of the pyramid. He tried again with the Bent Pyramid (c. 2600 BCE). The pyramid changes its angle about halfway up. The base of the pyramid has a slope of 55 degrees, but the upper part is 43 degrees, making the pyramid look mashed down from the top. Sneferu’s final pyramid, the Red Pyramid (2575-2551 BCE) was much closer to what he wanted. It was wider than the Collapsed or Bent pyramids, with a shallower pitch to the sides, but it was stable.

Parthenon, Athens, Greece (447 – BCE to 438 BCE)

If there is any building that symbolizes ancient Greece, it is the Parthenon. Pericles had it built on the site of an earlier temple using 5,000 talents (about 3 billion USD) from the treasury of the Delian League (Greek city-states allied to fight the Persians). This was very controversial move. His political opponents were upset when he used public funds for the Parthenon project, but Pericles persisted. His masterpiece is the crown of the Acropolis Hill, with its fluted Doric columns and rising pediments. It was the temple to Athena, the patron goddess of Athens, the capitol of the Athenian city-state. The original Athena statue went missing long ago, and the roof of the Parthenon blew off in 1687 when the Turks used it as an armory during its war with the Venetians. A mortar hit the gunpowder and blasted the roof off the building.

Parthenon Secret: Optical Illusion

Architects Callicrates and Ictinus were really good at understanding how the human eye works when such a large building is constructed. From a distance, the columns of the Parthenon appear to be perfectly straight, balanced, and without deviation. But they are not. Imperfections in the human eye would make the columns appear distorted. To correct for this, architects made the columns a few inches wider in the middle. Because of this, people standing next to the columns would see them as perfectly straight, and reaching to the sky. Inside the temple, the large, open floor has a very slight, virtually invisible dip to make it look perfectly flat.

Parthenon Secret #2 – Vivid Color!

Today we see the Parthenon as a gleaming white marble building, its only decoration in the sculpture and friezes that are still standing. But back in the Hellenic period when it was built, the Parthenon was bright with vibrant colors. Researchers have studied traces of paint along the west cornice. They found the Greeks used a lot of paint on their buildings, even the temples we think of as uncolored. Their work revealed traces of green paint and several types of blue, including azurite and Egyptian blue. There were two types of red found, red ochre and red lead. The study also found two blacks, two whites, and a yellow paint. Painters mixed pigment with beeswax and heated to bind the paint layers, called an encaustic technique. The Greeks loved color, and the white marble we see today is really just the base.

Great Wall of China (began 7^th Century BCE)

Despite the legend, the Great Wall of China is not actually visible from space – that’s a rumor started in 1923 by National Geographic magazine. But it is an impressively long wall, stretching about 21,196 kilometers (13,171 miles). It moves with China’s mountainous terrain, curving up and around the hillsides, and incorporates natural barriers like rivers and cliffs. Guard towers periodically interrupt the wall’s flow. Defensive parapets and crenels top the wall along its ‘superhighway.’ A walkway along the top of the wall allowed soldiers, messengers, and equipment and uninterrupted path between strategic points, moving armies and troops quickly along the terrain. The Great Wall has come to symbolize China’s empire and its long-term strength, even if it wasn’t completely successful in keeping out all enemies (especially the Mongolians!).

Great Wall of China Secret: It’s Edible! Sort Of… Please Don’t Eat It.

Slaked lime was a key ingredient in the construction of the Great Wall of China. But Zhejiang University scientists have discovered a surprising additive: Congee, a sticky rice porridge. The sticky rice dish contains amylopectin. When that combines with calcium carbonate, it creates a “compact microstructure” so strong it can withstand natural events like storms and earthquakes. While its strength is considered average when compared to other mortars, it is water resistant, shrinks less, and the chemicals in the mortar actually make it stronger over time. This was the first true composite mortar known to history. While the use of sticky rice for Great Wall construction was controversial at the time, because it took rice away from the workers and used it in mortar instead. Despite the hungry, resentful workers, the sticky was incredibly successful. The mortar is still so strong in places that weeds cannot grow through it.

Pantheon, Rome Italy (c. 118 – 125 CE)

Rome’s Pantheon is the largest unsupported concrete dome in the world, a startling record since building technology has come so far. Its dome has presided over the city of Rome since the time of Hadrian, who built it to honor multiple Roman gods. The niches around the building once held statues of various gods. The oculus, a 9 meter(29 foot) round opening at the peak of the dome, is the main source of light and fresh air. There is no glass in the oculus; when it rains, the floor gets wet. Fortunately, there are drains in the floor to help with pooling water. During certain times of the day and year, the sun shines through the oculus like a spotlight, shining on (or just above) the statues, highlighting each one in turn. These are just the famous features. The Pantheon is full of unsolved secrets.

Pantheon Secret: It Has The Wrong Name

The inscription on the Pantheon proudly proclaims, “Marcus Agrippa Lucii Filius Consul Tertium Fecit.” This ‘signature’ translates to ” Marcus Agrippa, the son of Lucius, three times consul, built this.” But that is not right. Agrippa’s temple at that site, dedicated to Augustus’s Actium victory over Antony and Cleopatra, burned down. He never replaced that temple. The Pantheon is a ‘replacement temple.’ Emperor Domitian had another temple built in its place, one that worshiped multiple gods, but that burned down, too. Agrippa rebuilt it, but curiously put Agrippa’s name on it instead of his own. He did not even mention Domitian. But Hadrian may not have full claim. Some of the Pantheon’s bricks are stamped with a date that shows at least part of it was built during Trajan’s reign and finished under Hadrian. Trajan was famous for his large public projects; could the Pantheon be one of them?

Pantheon Secret #2: Making a Concrete Ceiling Lighter

The Pantheon’s concrete domed ceiling is an engineering marvel. Roman engineers knew a concrete dome would be far too heavy. And nobody wanted a massive building collapse. To help reduce the weight, designers used both art and construction secrets. First, they used a, artistic coffered ceiling. Coffers are square indentations that give the ceiling some visual interest. Every square inch of concrete removed to create the coffers takes a little bit of weight off the dome. Second, the dome is a little thinner as it goes upward in height; it’s thicker at the base than at the top. Third, the oculus not only let in light and air, it also reduced the concrete in the ceiling. Finally, the most hidden secret is how the Romans blended hollow jugs, or amphora, in the concrete. The concrete was still super strong, but it lightened the amount of used in the dome.

Taj Mahal, Agra, India (1632 – 1648)

In 1632, Shah Jahan I of the Mughal Empire commissioned architect Ustad Ahmad Lahori for a very special project. He lost the love of his life, wife Mumtaz Mahal, who passed away after giving birth to their 14^th child. He wanted to create a mausoleum that would resemble the paradise Mumtaz Mahal was certainly living in the afterlife. Construction lasted for 22 years, but resulted in one of the most ornate, delicate buildings of the Mughal Empire. The mausoleum would become one of the most famous buildings in the world, the Taj Mahal. The white marble cladding features colorful inlaid stonework. Carved stone decorations look like royal icing on a delicate cake. The four minarets and the onion dome symbolize the Mughal Muslim traditions of the Empire. About seven to eight million people visit the Taj Mahal each year.

Taj Mahal Secret: It Is a Series of Optical Illusions

The Taj Mahal’s design is a bundle of optical illusions. When visitors enter the grounds, they pass through the Royal Gate. This gate serves as a visual frame for the building and makes the building look huge and close. Once through the gate, visitors see the Taj Mahal in full view at the far end of a huge garden. Walkways divide the garden into four sections. At the intersection of these walkways is a reflecting pool that gives a ‘flipped’ view of the mausoleum. The Taj Mahal is placed at the end of this garden, not at the center, to allow visitors to take in the whole building at once. As visitors walk the path toward the building, it actually appears to get smaller, as if it is moving away.

Taj Mahal Secret #2: The Towers Would Collapse Outward

The Taj Mahal is flanked at its four corners with tall minarets. These minarets reflect the Mughal Muslim tradition yet could be a real problem if India’s tectonic plates act up. Designers made the minarets lean slightly away from the building, so they would fall into the garden during an earthquake, not onto the building. In addition to protecting the building, the leaning minarets are an optical illusion. By leaning them outward, people looking at them from the ground see them as straight up and down. This is a trick of the eye; if they actually were straight up and down, the eye curves it, This is the same thing that happened with the Parthenon’s columns. So the minarets at the Taj Mahal accommodate this trick of the eye and tries to save it from earthquake. The designers had a lot of foresight!

Ise Inner Shrine (4^th Century BCE)

Also known as the Ise Jingu, the Ise Inner Shrine is the most sacred Shinto shrine in Japan. The Shrine is dedicated to many Shinto spirits. The main shrine is dedicated to the sun goddess Amaterasu. Its design is based on rural Japanese granaries from the Yayoi period (300 BCE to 300 CE). The building lies on a raised floor platform, with pillars sunk deep into the ground to support the building with a stable foundation. The “heart pillar,” shin no mihashira lies at the structure’s center. The thatched gable roof features the wood chigi poles and katsuogi that create distinctive, making the roof beams look like they are flying into the sky. The shrine is a pilgrimage destination for the Shinto religion, and twice a year it hosts the Kagura Festival to celebrate traditional Japanese dance, theater, and other arts.

Ise Inner Shrine Secret: Renewed Every Twenty Years

In 686 – 697 CE, under Empress Jito, a ritual started that continues to this day. Every twenty years, the Ise Inner Shrine, including the main Amaterasu shrine, 15 other shrines, the Uji Bridge, and the torii gate are torn down. It is then rebuilt in almost the exact same way, but on a different site within the Shrine. This cycle represents the Shinto idea of death and renewal and how nothing is permanent. It keeps old architectural traditions and skills alive. But it is also practical. The Ise Inner Shrine is a wood and thatch building, prone to weathering and water damage. Renewing the building helps keep the design the same while the wood is always fresh and new. The rebuilding uses about 10,000 cypress trees from the Shrine’s dedicated forest. In 2013, with full ceremony, the old shrine was taken down and replaced, continuing this cycle.

Temple of Kukulcán, Chichen Itza (8^th – 12^th Century CE)

Chichen Itza was one of the great Mayan cities of the Postclassical era (950 – 1511). At the heart of the city, near its sporting arena and observatory, is the Temple of Kukulcán, a large, nine-stepped pyramid dedicated to the feathered serpent god. On each side of the pyramid, a 91-step, very steep staircase brings visitors from the ground to the temple at the top. Unlike the Egyptian pyramids, the Kukulcán temple was never meant for entrance; there are no tunnels or burial chambers. It only needed to loft priests toward the skies. The temple was the exclusive domain of priests, elevated so they could perform sacred rituals closer to the heavens. Twice a year, according to legend, Kukulcán comes down from the heavens. The god then blesses the thousands of people who gather to see him, and heads down to the underworld (Xibalba).

Temple of Kukulcán Secret: There’s a Large Snake Coming Right At You

Kukulcán actually does make an appearance twice a year. The sun has to be shining and in just the right spot. During the spring and autumn equinox, the sun hits the stepped portion of the pyramid , casting a shadow against the tall, steep staircase wall. The shadow stops at the sculpted snake head at the base of the staircase. This looks like a serpent slithering down the side of the building. As the sun moves across the sky, shadows change to give it slow ‘movement’ as the day moves into night. Whether the illusion was designed on purpose or a happy coincidence is a mystery. When the crowds gather to see Kukulcán and receive his blessing, they are actually seeing the phenomenon of his moving from the heavens into the underworld, through optical illusion and good sunlight.

Brooklyn Bridge (1883)

Moving into modern times, the Brooklyn Bridge is a new world wonder. Before the early 1880s, getting across the East River from Manhattan to Brooklyn was a chore; it was by ferry, a slow, labor-intense process. City officials decided a bridge would better move traffic. John Roebling won the contract for the bridge design. He had developed a strong, stable suspension bridge using wire cable stays and stiffening trusses to create a deck. He used caissons to create the foundation of the suspension towers, a new technology with airtight chambers secured to the river bottom with large granite weights. The caissons had pressurized air to keep river water out, which gave many workers the bends when they emerged from the depths. Still, it was a technological marvel In the end, Roebling’s work has become a symbol of New York City and has provided safe passage for over 140 years.

Brooklyn Bridge Secret: Wine Cellars in Brooklyn Bridge

When John Roebling designed Brooklyn Bridge, he had a creative solution to two problems. First, how the city would pay for the $15 million bridge. Second, how to avoid disrupting two successful liquor businesses located on the land he needed to build the new bridge. To solve these dilemmas, he included two wine cellars and other vaults in the caverns below the bridge and rented them to vendors. The vaults held alcoholic drinks starting in 1876, before the 1883 bridge opened. They were dark, cool, and consistently a cool temperature. Rent would not cover all the construction costs, as there were not many vaults available. Yearly rent varied, some paid $500, others $5,000 each year, but it certainly helped offset the expense. Today the vaults are storage units, but some lucky few get permission to tour this hidden history.

Fallingwater (1936)

By the time Frank Lloyd Wright designed Fallingwater in Mill Run, Pennsylvania, he had a reputation for innovation and going against architectural norms. He defied the Victorian architectural tradition of designing tall buildings with lots of closed-off interior rooms. Instead, he created the Prairie style out of his love of nature and Japanese architecture. He would not stop at Prairie style. He adapted to modern – and postmodern – architecture as the decades progressed. Wright’s Fallingwater design is hailed as one of the most innovative of his career. The work was commissioned for Pittsburgh merchant Edgar “E.J.” Kaufman, who was particularly fond of a waterfall at a remote vacation spot. He hoped to build his home overlooking that spot. Wright figured out how to incorporate the waterfall into the design. His cascading cantilevers and windows that used the forest as decoration created a union between building and nature.

Fallingwater Secret: A masterpiece of procrastination

The design of Fallingwater was more like a student who leaves their homework for the night before it is due. Kaufman commissioned Wright to draw up the Fallingwater plans and had the land surveyed. But in true Wright style, he just didn’t do the work. He would tell his client he was “working on the plans.” Nine months later, Kaufman was in Milwaukee. Having not seen any drafts, he told Wright he was coming to Taliesin, Wright’s home and studio in Spring Green, Wisconsin. Wright, knowing it was a 140-mile drive from Milwaukee, had nothing to show his client. He had to work fast. Wright apprentice Edgar Taffel, who sharpened Wrights’ pencils like a NASCAR pit crew, said, “The design just poured out of him.” He drew the plans in two hours, in time for Kaufman’s arrival. One of the world’s most famous building is a rush job.

Chicago Carbide and Carbon Building (1929)

The Carbide and Carbon Company, developers of dry cell batteries, wanted a new headquarters to house their Chicago regional offices. What they got was an architectural landmark. The Carbide and Carbon building in Chicago sits along the coveted real estate on Michigan Avenue, about a block and a half north of Millennium Park. It was designed in 1929 by the sons of the prominent Chicago architect Daniel Burnham, Hubert and Daniel Jr. The building features Art Deco style from top to bottom, with its geometric details and vertical artistic details. Most of its 37 stories are clad in green terra cotta and black granite. Toward the top, near the tower at its peak, the building starts showing its glamorous side. Its geometric details boast marble and 24K gold leaf accents.

Carbide and Carbon Building Secret: It may be a reaction to Prohibition

The Carbide and Carbon Headquarters was designed and built during the 1920s, when Prohibition laws in the United States were in full swing. There is a persistent rumor that the Burnham brothers designed their masterpiece to tell the world exactly what they thought of the Prohibitions laws in the United States during the 1920s. The base of the building is a bright green, like a champagne bottle, a strange color scheme for a skyscraper at the time. Bright, shining gold coats the upper stories. The building tapers quite a bit toward the top. These elements look like the neck and foil wrapping of a champagne bottle. The Burnham brothers never confirmed or denied that they designed the rumor that they designed their building like a champagne bottle as an architectural middle finger to Prohibition. But the building’s looks and the timing are just a bit coincidental.

Empire State Building (1931)

The Empire State Building is one of New York’s most famous landmarks, an Art Deco masterpiece, and a climbing toy for King Kong. Built in the early years of the Great Depression, it was the first building to reach over a hundred stories tall. While the Empire State Building typified 1930s glamour, it lacked one important feature: tenants. For most of the 1930s, tenants were scarce during one of the country’s worst economic crisis. People called it the “Empty State Building.” But it did not stay that way for long. The offices filled up. By 1946, the Empire State Building was one of the world’s most profitable building. To this day, the observation decks draws over 4 million visitors a year, generating more revenue than the office rents! In 2007, the Empire State Building ranked first on the American Institute of Architects list of American’s Favorite Architecture.

Empire State Building Secret: Zeppelin parking station

Today the 102^nd floor is a spectacular, although small, circular observation deck. It did not start this way. The original design used the space as a lobby and dock for the new airships gaining popularity. New York officials were so hopeful this could happen they distributed renderings of an airship docked that the Empire State Building’s tower. Airships would dock at the 102^nd floor tower, passengers exit via gangplank, and enter the lobby. Zeppelin commander Hugo Eckener dismissed the idea, noting zeppelins took a large grounds crew with lots of tether rope, not just a small connection to the tip of a building. Additionally, moving passengers on a ramp between an airship and port at that height is extremely dangerous. In 1931, a private airship owner tried to dock at the port. The connection lasted three minutes. 40-mile-per-hour winds made it impossible to stay. Officials scrapped the airship idea.

Empire State Building Secret #2: A Plane Flew Into It

Army combat veteran and pilot Lieutenant Colonel William Smith was flying a B-52 bomber to LaGuardia Airport on July 28m, 1945, when he lost his bearings in heavy fog. Despite his best efforts and a few near-misses of other skyscrapers, he hit the 78^th and 79^th floor of the Empire State Building. There was an explosion, and petrol from the plane lit some floors on fire. A piece of the engine cut into the elevator shaft and through cables on two elevator cars. The cars dropped from the 75^th floor to the subbasement, a drop of over one thousand feet. Elevator operator Betty Lou Oliver miraculously survived the drop, the car perhaps being cushioned by severed cables coiled at the bottom of the shaft or a buildup of compressed air from the rapid drop. The crash killed Smith, his crew, and eleven people inside the building.

National Cathedral, Washington DC (1907 – 1990)

In 1907, President Theodore Roosevelt laid the cornerstone that began construction on a grand national project, the National Cathedral in Washington DC. Architects used Gothic form for the Cathedral, giving the impression that it has always been around. It has a cruciform layout, resembling the Christian cross when looked at from above. Buttresses and flying buttresses support the tall cathedral walls in Gothic style. There are three rose windows, vaulted ceilings, 215 stained glass windows, and pointed arches flanking the entrance. It stands as the Westminster Abbey or the Notre Dame of the United States, a cathedral for the people. It is a place for sacred events. The National Cathedral has hosted some Presidential inaugurations, presidential funerals, funerals for others of prominent national figures such as Neil Armstrong and Helen Keller, and memorial services for national tragedies like the September 11 attacks.

National Cathedral Secret: An unexpected visitor

Walking around the Cathedral to the northwest tower, visitors may notice something strange and startling. Looking down on them from high above is none other than Darth Vader, villain of the Star Wars movies. Darth Vader is a grotesque, which deflects water away from the building (this is different than a gargoyle, which is an active waterspout). In the 1980s, a National Geographic World contest asked children to design grotesques for the Cathedral. 13-year-old Christopher Rader submit a Darth Vader design, winning third place for his idea. Hay Hall Carpenter scultped the grotesque, with Patrick Plunkett carving it from stone. In 1986, Darth Vader became a menacing permanent part of the National Cathedral’s tower. As AV Club writer Reid McCarter puts it, Darth Vader is there “…to scare the faithful with a fate far worse than eternal damnation: Getting Force-choked by a bipedal air purifier.”

National Cathedral Secret #2: A Piece Of The Moon

Along the south aisle of the Cathedral, one stained glass window does not follow the classical Gothic and religious themes common in most cathedrals. The Space Window celebrates the achievements of NASA and the exploration beyond Earth. It features stars, orbiting planets, and illustrates Earth’s connection to the depths of space. Dr. Thomas Paine, NASA administrator during the Apollo program, donated the window. Apollo 11 crew members Neil Armstrong, Edwin “Buzz” Aldrin, and Michael Collins presented a piece of moon rock at a Cathedral ceremony in 1974. The seven gram piece of the moon, is from a sample collected in the Sea of Tranquility during the Apollo 11 moon landing mission. It is a basalt rock section that contains the mineral pyroxferroite, something not discovered on Earth.

Where did we find this stuff? Additional sources

10 architecture marvels of the Ancient World and the things we don’t know about them. Ojaswita Saksena, Re-Thinking the Future. (n.d.).

Airship Docking State on top of the Empire State Building. CityBeauitifulTours, City Beautiful Bloc, 25 January 2021.

Eight secrets of the Taj Mahal. Lisa Cheng, Smithsonian Magazine. 14 February 2017.

A husband’s love built the Taj Mahal – but cost him an empire. Eva Fernandez Del Campo, National Geographic, 10 February 2022.

The optical illusions that make the Parthenon perfect. John Leonardm, Greece Is, 12 January 2018.

Roebling and the Brooklyn Bridge: Today in History. (n.a.) Library of Congress, June 12 (n.y.)

Sticky rice holds ancient Chinese buildings together. Kate Ravilious, National Geographic. 9 June 2010.

Sticky rice mortar, the view from space, and more fun facts about China’s Great Wall. Lorraine Boissoneault, 16 February 2017.

The day a bomber hit the Empire State Building. Joe Richman, NPR.org, 28 July 2008.

This Japanese Shrine has been torn down and rebuilt every 20 years for the past millennium. Rachel Nuwer, Smithsonian Magazine, 4 October 2013.

When the Parthenon had dazzling colours. Natalie Haynes, BBC.com, 22 January 2018.

Yes, Darth Vader looms over Washington National Cathedral. Michael Walsh, Nerdist, 25 February 2022.