The pyramids' bases are square with four sides. Some of them, like as the well-known Great Pyramid of Giza, have each corner facing a distinct cardinal direction: north, east, south, and west. The Great Pyramid's alignment is virtually perfect, being only 0.067 degrees counterclockwise from the perfect cardinal alignment. As for the other pyramids, they too are perfectly aligned.
The reason all the pyramids are aligned perfectly is because they were built by the Egyptians using celestial coordinates. The base of a pyramid is always leveled using the altitude of the sun at midday during the summer solstice. This would be the exact height of the sun in the sky to an accuracy of about 1 degree. If there were any error, it would mean failure of the king to offer sacrifices at the right time of year, which was not considered acceptable.
The horizon on which they stand is also level, so the pyramids themselves are perfectly vertical. In fact, very few buildings throughout history are completely vertical!
Finally, the pyramids were not just built but also designed by the Egyptians to reflect the solar system. The placement of their chambers and corridors follow a precise geometry based on the planets in our solar system. For example, the corridor between the second and third levels of the pyramids at Giza passes through the center of Venus when seen from space.
This shows that the Egyptians had a sophisticated understanding of astronomy.
Giza's pyramids face the four cardinal directions: true north, true south, east, and west. Their entrances are all on the north side, whereas the pyramids' temples are on the east side. The southern sides are mostly rubble now.
North is at the top of the diagram. East is to the right. South is down at the bottom. West is across from east at a slight angle.
Each pyramid is an altar to the pharaoh who built it. They were used for ceremonial purposes, especially during the annual flooding of the Nile River. The pharaoh was believed to live on after his death, so they were important sites for showing respect to him.
The Giza Pyramids were built for King Khufu (c. 2670-2610 B.C.) by a team of more than 5,000 workers over approximately 20 years. He was the father of Queen Henutsen and the husband of Ahhotep. His wife had several names which means "the good mother."
Khufu's pyramid is the largest of the three pyramids at Giza. It is also the only one that is completely intact. The other two pyramids are partly collapsed. Still, they are large enough to be seen from miles away on a sunny day.
Each side of the Great Pyramid rises at a 51.5-degree inclination to the summit. Not only that, but each of the sides is almost precisely aligned with true north, south, east, and west. The pyramid's sides are also equal in length from base to peak, which means they can be used as relative measures for other structures.
The three smaller pyramids at Giza were built by King Khafre (2589-2566 B.C.). The smallest of these is called the Meidum Pyramid and it is nearly identical to the Great Pyramid with respect to size and shape. The second one, named Menkaura, was built for his wife. It is not as large as the Great Pyramid or the Meidum Pyramid but it does contain two chambers separated by an inclined wall. The third king, Khafre, had this pyramid built for himself. Like the others, it has two chambers separated by an inclined wall.
Angles are measured in degrees. A right angle is 90 degrees while a straight line is perpendicular to another line. An angle is formed when two lines or surfaces meet at a point or area without overlapping. Angles can be classified as either acute or obtuse. Acute angles have their tops closer together while obtuse angles have their tops farther apart. With angles, more than one method can be used to classify them.
Contrary to popular belief, the Great Pyramid is an eight-sided building, not a four-sided construction. From base to tip, each of the pyramid's four sides is evenly separated by extremely tiny concave indentations. The average width of these features is about the same size as the thickness of a sheet of paper. In fact, if you drew all the lines connecting pairs of opposite corners, they would form a grid pattern with squares just large enough to fit inside the pyramid.
The reason why so many people think that the Great Pyramid is built of 4,000 stones is because it is based on the number 4,000. However, this isn't true; it is based on the number 40. Each side of the pyramid is exactly 40 feet (12 m) long.
In addition to being an even number, 40 is also very close to half of 100, the total number of holes found in each side of the pyramid. Since half of 100 is 50, the Great Pyramid is composed of two sets of columns with 10 holes in each set. There are also two other closely spaced sets of columns with only 9 holes in each. These three groups of columns provide support for the roof of the pyramid. The only solid piece of the structure is the foundation, which is made up of 2 layers of stone slabs.