It's still a wonder how the ancients ever built it
The Great Pyramid of Giza
Location: Cairo, Egypt
Built about 2560 BC
The Great Pyramid of Giza is the grandfather of the Seven Wonders of the World. It is the oldest, the biggest and the only one still standing today.
The ancient Egyptians believed that their kings were living gods. When an important king died, his body was mummified and buried in a chamber deep inside a stone pyramid. The Great Pyramid of Giza was built to house the tomb of the Egyptian pharaoh Khufu.
It took a workforce of 100,000 slaves and builders over 20 years to build Khufu's pyramid. It was the biggest structure ever to be built in Egypt. When it was finished, it rose almost 100 metres above the desert sands. It was the tallest structure on Earth for more than 43 centuries.
Each of the four sides of the pyramid lines up with the four points of the compass and each side is at a 51-degree angle. The structure is solid apart from the burial chamber in the middle and the passageways leading down to it.
The pyramid is made up of two million blocks of stone, each one weighing more than two tonnes. The pyramid has enough stone slabs to build a three-metre high wall around the perimeter of France.
Experts have argued for centuries about how the Great Pyramid was built. There was no big machinery in those days, so how did the builders set such heavy stone blocks into perfect position? It is probable that each huge block was dragged up earth ramps built like solid scaffolding around the pyramid and then eased into place by some sort of crane.
No one knows exactly how the Great Pyramid was constructed, but that hardly comes to mind as you stand in front of the only surviving wonder of the world. Will any buildings built today last for four and a half thousand years? Now, there is food for thought.