Every person with an insatiable curiosity is quite familiar with most of the wonders of the world. There are seven wonders of the world based on popularity from a survey that was conducted among 100 million people. The list includes the Great Wall of China (China), Christ the Redeemer (Brazil), Machu Picchu (Peru), Chichen Itza (Mexico), Taj Mahal (India), Petra (Jordan), and the Roman Colosseum (Rome).

Apart from the winners, there were 14 more wonders that had made it into the final round. Nevertheless, all the 21 monuments and architectures in the final rounds are fascinating. From buildings which were built more than 2,000 years ago with intricate engineering to the buildings built with exquisite architecture in the medieval times, these wonders of the world include everything exquisite created by man. Many of us are more than familiar with all the major facts that make the wonders of the world special. Yet, there are some facts which most of us are not aware of. Below are some of such lesser-known facts about some wonders which will surely amaze you.

1 It is illegal to take a picture of the Eiffel Tower in Paris when its lights are on.

The Eiffel tower is the living embodiment of beautiful engineering. During the night, when the lights of the Eiffel Tower are on, one can barely resist taking a picture. However, taking a picture of this wonder at night is a violation of the artist’s copyright. The agency that services the tower, Société d’Exploitation de la Tour Eiffel (SETE), officially states that the lights on the tower are an artistic work. The lights are protected by European copyright law. In other words, all variations of lights on the Eiffel Tower such as the golden illumination, twinkling, beacon, and even lighting during special events are protected.

Additionally, according to the European Union Law, the copyrights of any artist expire 70 years after the artist’s death. The lights were installed by an artist Pierre Bideau, who is alive, so it is safe to assume that copyright law might be around for another decade. The use of an image of the Eiffel Tower with lights on is only acceptable with the appropriate authorization from SETE. Although, any pictures taken from the top of the tower are copyright-free. (source)

2 The Leaning Tower of Pisa has survived at least four strong earthquakes.

Some of the questions that arise at the first sight of this wonder are, “Why is it leaning?” and “Will it fall?” However, it would completely astound you find out that this tilted tower has made it through at least four, strong earthquakes. Even though it was designed to be built perfectly vertical, the Leaning Tower of Pisa started to lean even during construction. The reason for the lean is the soft soil and the tower’s unstable foundation. Ever since the construction had started around 1173, at least four strong earthquakes have hit the city of Pisa. Surprisingly, this vulnerable-looking tower survived them all.

The secret to this tower’s strength is dynamic soil-structure interaction. The soft soil underneath the tower doesn’t let the tower above vibrate with the ground motion caused by the earthquakes. Miraculously, the very soft soil that causes the lean is what has kept this tower safe from the earthquakes. (source)

3 To this date, we are not quite sure about how the Great Pyramid of Giza was built.

The Great Pyramid of Giza is the oldest of the Seven Wonders of the Ancient World. Additionally, it is also the only ancient wonder that has remained intact. Built around 2560 BCE, the Great Pyramid of Giza was the tallest building for over 3,800 years. About 2.3 million stone blocks were used in the construction of this pyramid. When gazing on its beauty, one can’t help but wonder how this marvel was built. Nevertheless, we have no conclusive proof so far about how it was built.

Many scientists have their theories, but all of them remain unproven. Some experts have a theory involving a system of ramps. Many others have claimed that the system involved a linear staircase. The most accepted belief is that the huge stones were moved from a quarry and lifted into place manually. All these above-mentioned theories are based on conjecture. As a result, just how the Great Pyramid of Giza was built still remains a mystery. (1)

4 Almost 30% of the Great Wall of China has disappeared since it was built.

The Great Wall is made of bricks and is a structure that stretches out for miles. Over the years, 30% of the wall has disappeared because of adverse weather conditions, the harm done by tourist activities, and robbery of the bricks by the local people to build their houses. Of the 6,300-km wall built during the Ming Dynasty, only about 4,338 km of the wall still stands intact today.

Besides, a survey by the Great Wall Society also reported how the plants growing in the walls are harming it. Some experts claim that continuous perennial exposure to wind and rain is also making the wall weak. Some towers have become so shaky that they might collapse in a single rainstorm. It is predicted that more than 37 miles of wall will disappear in the next 20 years due to the sandstorms. Sadly, all these things are causing damage to the longest human construction artifact in the world. (1, 2)

5 The great Colosseum of Rome was once used as a cemetery and even a castle.

This largest amphitheater in the world is situated in the center of the city of Rome. It had a capacity of 50,000 to 80,000 spectators. This building was used for entertainment in the early medieval era. Most importantly, it was used for gladiator contests, animal hunts, mock sea battles, re-enactments of famous battles, and classical mythological dramas.

Though the monument is substantially ruined, it still is listed in the list of The New Seven Wonders of the World. By the late 6th century, this amphitheater was converted into a cemetery, and the vaulted spaces of the Colosseum were rented out as shops. It was not until 1200 when the Frangipani family took over the Colosseum to use it as their castle. The beautiful amphitheater that we know today was used over the centuries in various capacities. Currently, only one-third of the original Colosseum stands which is a major tourist attraction but is also used for various Roman Catholic ceremonies. (1, 2)

6 The land on which Chichen Itza is built, one of the Seven Wonders of the World, was privately owned until 2010.

Chichen Itza, the city built by the Mayan people, is located in the Yucatan State of Mexico. It is one of the largest Mayan cities of the ancient past. Moreover, some data claims that this was also one of the mythical cities referred to in Mesoamerican literature. The buildings of this city have a very unique architecture which is a result of its diverse population.

Surprisingly, the land, on which this wonderful city was built was privately owned until 29 March 2010. The Barbachanos had purchased this land in 1944 from an American archaeologist, Edward H. Thompson, and have owned it since. However, the constitution always claimed that the archaeological monuments forever belonged to the nation. The land of the city of Chichen Itza was privately owned for around 500 years. Nevertheless, in 2010, the land was sold to the Yucatan State, Mexico. (source)

7 An object bigger than an average blue whale was recently found buried in the sand near the caves of Petra.

Petra is a historical city situated in the southern Jordan. This city is believed to have been settled in around 9000 BCE. Over the course of many years, many countless civilizations have inhabited Petra or have interacted with the civilizations that inhabited Petra.

A massive monument dating back almost 2,150 years has been found buried underneath the ground near Petra. The monument is almost 184 ft. by 161 ft. As it is buried under the ground, this structure is hidden and hard to reach. The monument is buried almost at the center of the city.

The most startling fact is that this structure was missed by previous surveys and has no mention anywhere in history. The monument isn’t connected to Petra and is mysteriously hidden out of reach. This new monument adds to the existing mystery of the existence of these caves. (1, 2)

8 The mysterious Stonehenge took around 1,500 years to complete.

They might just look like a couple of rocks placed on a plain, but they are more than that. Stonehenge, a prehistoric monument in England, consists of a ring of standing stones. Each stone weighs around 25 tons and is up to 15 ft. long. Archaeologists believe that it was constructed in stages somewhere between 3000 and 2000 BCE.

According to the facts provided by radiocarbon dating, many experts believe that the site took approximately 1,500 years to complete. Two types of stones were used to make this monument – large sarsen stones and smaller bluestones. Transport was one of the several stages of construction of Stonehenge. Some of these stones were transported from more than 250 km away. Meanwhile, their means of transport still remains a mystery. (1, 2)

9 The area encompassed by Angkor Wat is larger than the area of the world’s smallest country.

Angkor Wat is one of the largest religious monuments in the world and is located in Siem Reap, Cambodia. It was originally constructed as a temple dedicated to the Hindu god Vishnu but was gradually transformed into a Buddhist temple. In other words, this monument plays a vital role in two religions – Hinduism and Buddhism. This glorious monument is well known for its grandeur, and it is also displayed on the national flag of Cambodia. It is the prime tourist attraction of the country.

Surprisingly, this temple complex spans over about 162.6 hectares (402 acres, 1,626,000 square meters). No wonder Angkor Wat holds the Guinness World Record for being the largest religious monument in the world. The area of Angkor Wat is almost four times as big as the world’s smallest country, Vatican City. The Vatican has an area of only 44 hectares. One of the eye-catching features of Angkor Wat is the moat that surrounds it. This huge complex is surrounded by a 5-km-long moat that is 190 meters wide. Most of the area of the complex is surrounded by forest. (1, 2)

10 Unlike conventional buildings, the buildings in the city of Machu Picchu are built without the use of mortar.

Situated 7,970 feet (2,430 meters) above the sea level, Machu Picchu is indeed an unparalleled engineering feat. This city of the Incas was voted as one of the Seven Wonders of the World in the year 2007. Incas, the civilization that made these structures, made them without any use of mortar.

The people who built these structures were the masters of a technique of building called “ashlar.” The stones used are carved to perfection and fit with each other like the pieces of a jigsaw puzzle. All stones perfectly fit together. The Incas also built appropriate terraces and stone chips to drain water efficiently. Also, multiple canals connecting this city are responsible for irrigation and prevent erosion. These structures have stood strong throughout hundreds of years despite heavy rainfall, erosion, mudslides, landslides, and flooding. Even at an unbelievable height and with harsh weather, the buildings in this city have stood strong for 500 years. (source)