Great Pyramid

Start construction about 2700BC and estimated completion is around 2500BC.

At the city of Giza at necropolis of ancient Memphis, and today part of Greater Cairo, Egypt.

The Great Pyramid was built by the Egyptian pharaoh Khufu of the Fourth Dynasty around the year 2560 BC to serve as a tomb when he dies. The tradition of pyramid building started in Ancient Egypt as a sophistication of the idea of a mastaba covering the royal tomb. It took around 20 years to complete the construction. At the earliest time of Egypt, mastaba was the permanent residence of the pharaoh when a pharaoh is dead. Later in the second to the third dynasty, the Egyptians have the concept that pharaoh is going to be god when he died and have to be buried in pyramid.

The Great pyramid was 145.75m, but it lost about 10m off its top after thousands of years of weathering. It was the tallest structure on Earth until the completion of Eiffel Tower. It was covered with a casing of stones to smooth its surface.

The structure consists of approximately 2 million blocks of stone, each weighing more than two tons. The sloping angle of its sides is 54 degrees 54 minutes. Each side is carefully oriented with one of the cardinal points of the compass, that is, north, south, east, and west. The horizontal cross section of the pyramid is square at any level, with each side measuring 229 m in length.

The entrance of the pyramid is located at the north face. There are a number of corridors, galleries, and escape shafts either lead to the King's burial chamber, or were intended to serve other functions. At the heart of the pyramid is the King's chamber and it only can access through the Great Gallery and an ascending corridor. There is a number of sharp-edged stone over the door and it fit so well.