One of the seven wonders of the ancient world, the pyramids of Giza have fascinated mathematicians, architects, historians and more than 14 million visitors annually. While construction of the symmetrical structures still draws debate and lengthy discussion, the materials used and cost to accomplish such a feat has been assessed.

Today’s cost of the 2,300,000 limestone blocks used to build Pharaoh Khufu’s Great Pyramid amounts to $495 per block. Each block is estimated at 2.5 ton and the cost per ton is just under $200, making the total cost for the pyramid itself, $1.14 billion. Add in labor, transportation and other costs, the largest pyramid of Giza would cost approximately $1.2 billion according to The Richest.

The pyramids of Giza were tombs build for three different pharaohs around 2550 B.C. The oldest and largest of the trio was built for Khufu, second king during the fourth dynasty. Khufu’s pyramid at one time reached 481 feet, but today is approximately 451 feet.

It covers more than 13 acres, and the sides rise to an angle of 51 degrees.

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The second pyramid was built for Pharaoh Khafre, fourth king during the fourth dynasty. Khafre’s pyramid is 471 feet tall according to Britannica.

The third pyramid was built for Pharaoh Menkaure, the fifth king during the fourth dynasty. This pyramid is significantly smaller at 218 feet, but still towers over several small pyramids in the area.

Also in Giza, stands the 66-foot Great Sphinx. Carved out of limestone, the sphinx has the face of a man and the body of a lion, thought to guard important areas for tombs and temples. Eventually, the sphinx was even honored and worshipped for its role in Egyptian protection.

Pyramids weren’t built as stand-alone structures but included temples, chapels and other tombs. Smaller pyramids on the complex were used to bury other members of the royal family. While the burial process and tradition is guarded in mystery, archeologists have found enough evidence to understand the importance of the pyramids and other surrounding structures.

A tour of the Great Pyramid reveals two interior burial chambers, one for the queen with smooth limestone blocks, a gabled roof and floor made of pink granite stone.

The other chamber was designated for the king, featuring unique inscriptions, limestone, granite and a granite slab used to house the sarcophagus.

Inside the pyramid, extractor fans were placed to circulate air and escape techniques were implemented for emergencies.

Throughout history, conversation has continued regarding how these great structures were created given the Egyptians limited tools.

Greek historian Herodotus estimated the Great Pyramid took 20 years to build and 100,000 men – farmers who worked in the off-season. However, modern archaeologists have found evidence that the site may have been worked year-round with a crew of 20,000.

According to the Smithsonian, Egyptians typically used copper tools like chisels, drills and saws which may have come in handy with a soft stone like limestone. The granite inside the pyramid and used in some exterior casing would have been more difficult.

What we do know, is that astronomy was used to keep workers oriented and one tomb painting reveals their practice of moving huge stone blocks on sledges and ramps to settle on their correct position. Each of the three pyramids in Giza align with the constellation of Orion.

Unfortunately, the major sites for grave robbers and looters haven’t left much to be discovered by way of bodies, jewelry, and other funeral goods today. Vandals have also stripped portions of the exterior limestone coverings.

As Egyptians realized the protection of the pyramid was jeopardized, they began burying kings in hidden tombs inside rock cliffs.

Compare the cost of the Great Pyramid back then to building one similar today. We have done just that in modern times, spanning from architectural research to actually building replicas.

The Luxor in Las Vegas for example is made almost entirely of steel at 350 feet, coming in third place for tallest pyramid in the world.

According to Culture Trip, the Luxor’s atrium was once the largest in the world and the building features a casino, restaurants, IMAX theater and show venue.

Calculating the Luxor with modern materials of steel and glass, it cost $375 million to build – a far cry from the $1.2 billion spent of the original version in ancient Egypt.

However, the grandeur and mystery behind the Pyramids of Giza remain. Egyptian kings continued to order construction on pyramids for years after the famous three, but those were much smaller in size and eventually, the need for a lavish burial in pyramid form waned.

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Sources: The Richest, Britannica, Smithsonian, Culture Trip