Spanning over a period of two thousand years, the ancient Egyptian civilization saw the rise of architectural genius, among other things, in the form of pyramids. The Giza Pyramid Complex, or the “Giza Necropolis,” is an incontrovertible example of this, and it was built while the woolly mammoths of Wrangel Island in the Arctic Ocean were still living.

The complex is home to three main pyramids  –  the Great Pyramid, the Pyramid of Khafre, and the Pyramid of Menkaure – along with smaller “queens’ ” pyramids and the Great Sphinx. It is definitely to no one’s surprise that the ancient Greeks considered the largest of these to be one of the Seven Wonders of the Ancient World. The Great Pyramid is now the only surviving artifact of the seven wonders after the Mausoleum of Halicarnassus sadly turned to ruins only 500 years ago.

The Great Pyramid of Giza was built as a tomb for the Fourth Dynasty Egyptian Pharaoh Khufu. The construction took 20 years, finishing in 2560 BCE, and utilized 2.3 million stone blocks weighing an average of 2.5 tons apiece.

Khufu chose to have the pyramid built on the plateau of Giza so that it would be visible far and wide. He called it “Akhet-Khufu” which means the “Horizon of Khufu.” The pyramid is estimated to weigh 5.9 million metric tons and has a volume of 2.5 million cubic meters (88 million cubic feet). According to French architect Jean-Pierre Houdin, if modern techniques were to be used to build the pyramid, it would cost an estimated $5 billion and require a workforce of 1,500 to 2,000.

Unlike what the Greeks thought, evidence suggests that the pyramid was built using paid laborers who would work three- to four-month shifts in lieu of taxes. They also received ten loaves of bread and a jug of beer each day for their work. The precise number of workers who worked on the pyramid is not known. While mathematician Kurt Mendelssohn suggested 50,000 men, Ludwig Borchardt and Louis Croon believed the number to be 36,000. However, it is estimated that around 4,000 workers quarried, hauled, and set the stone.

Originally, the pyramid was white and covered in highly polished limestone casing stones. After a massive earthquake loosened them in 1303 CE, the stones were used to build mosques and fortresses in Cairo by the Bahri Sultan.

In 2013, a collection of papyrus logbooks known as “The Diary of Merer” was discovered in a cave by a French mission led by Pierre Tallet of Paris-Sorbonne University. The text disclosed the limestone transportation work during several months from Tora to Giza, with two or three trips every ten days by around 40 boatmen who worked under Merer. Tora was an ancient mining town with the finest and whitest limestone throughout ancient Egypt.

An estimated 5.5 million metric tons of limestone was used for the Great Pyramid, and each stone had a slanted face. After the earthquake, many of the stones were used by Bahri Sultan An-Nasir Nasir-ad-Din al-Hasan to build mosques and fortresses. Later, in the 19th century, the Ottoman governor of Egypt, Muhammad Ali Pasha, had more casing stones removed to construct the Alabaster Mosque in Cairo. A few of the casing stones can still be seen on the pyramid to this day.

The inside of the pyramid houses the King’s Chamber, the Queen’s Chamber, the Grand Gallery, and the “Big Void.” A tunnel known as the “Robber’s Tunnel” created around 820 CE leads into the pyramid.

The King’s Chamber is made of granite and contains only the sarcophagus. Its roof is formed by nine stone slabs weighing a total of 400 tons. Above the roof are five compartments known as the Relieving Chambers that are believed to protect the King’s Chamber from collapsing.

The Queen’s Chamber is located halfway between the north and south faces of the pyramid. The chamber has three shafts at the end, one of which the National Geographic found using robots, and has a door with a copper handle. Beyond the door was a small chamber with red hieroglyphics on the walls.

The Grand Gallery is a 47-meter-long (153-foot-long) passage and provides access to the Relieving Chambers. The Big Void is a large empty space right above the Grand Gallery discovered in 2017 through muon radiography. Its purpose is as yet unknown. The Robber’s Tunnel was created by Caliph al-Ma’mun using a battering ram and cuts straight through the stones for 27 meters before turning left, leading to the Ascending Passage. The passage slopes upwards, leading to the Grand Gallery.

The Great Pyramid of Giza remained the tallest man-made structure in the world for 3,871 years until 1311 when the Lincoln Cathedral was built in England.

Originally, after the construction, the pyramid was 280 Egyptian Royal cubits tall that is 146 meters (480 feet). But due to erosion and the disappearance of the pyramidion, a capstone or obelisk at the top, its current height is 139 meters (456 feet). It held the record for the tallest structure to have ever been built until the construction of Lincoln Cathedral which measured 160 meters (525 feet) was finished. However, the building’s central spire was destroyed during a storm in 1549 and wasn’t rebuilt, transferring the record to St. Mary’s Church (151 meters) in Stralsund, Germany.

It isn’t just the pyramid’s height at that age that’s amazing, but also the workmanship and precision with the minutest error. Despite being a square of 230 meters (756 feet), the pyramid’s base is so flat that the error is just 15 millimeters. The four faces of the pyramid are aligned very closely to the four directions of the compass.

The last surviving of the destroyed other six Wonders was the Mausoleum of Halicarnassus built between 353 and 350 BCE as a tomb to the Satrap of the Achaemenid Empire Mausolus and his wife, Artemisia. It was destroyed due to recurring earthquakes between 12th and 15th century CE.

The list of the Seven Wonders of the Ancient World dates as far back as to the 1st and 2nd centuries BCE, though its current form was agreed upon during the Renaissance Period. Apart from the Great Pyramid and the Mausoleum, the other Wonders include the Colossus of Rhodes, the Statue of Zeus, the Temple of Artemis, and the Lighthouse of Alexandria. Sadly, earthquakes and invasions have destroyed them all, the Mausoleum of Halicarnassus was the last of the other six.

The Mausoleum, like the Great Pyramid, was a tomb built between 353 and 350 BCE for Mausolos, the satrap (governor) of the Persian Empire and his wife, Artemisia II in Halicarnassus, which is now Turkey. The structure was approximately 45 meters high and had sculptural reliefs adorning its four sides. Each side was created by a different famous Greek sculptor: Leochares, Timotheus, Bryaxis, and Scopas of Paros.

[Sources: Wikipedia, LiveScience]