Pyramids (Egypt), large structures with four triangular sides that meet in a point at the top, directly over the center of the pyramid’s square base. Ancient peoples in several parts of the world built pyramids, but the Egyptians constructed the biggest and most famous pyramids

The ancient Egyptians built more than 90 royal pyramids, from about 2630 bc until about 1530 bc. During that time, the pyramid form evolved from a series of stepped terraces that resembled the layers of a wedding cake to the better-known, sloped pyramidal shape.

The first pyramid, the Step Pyramid at Şaqqārah, was constructed during the reign of King Djoser (2630 bc-2611 bc). The largest pyramid is the one built for King Khufu, at the site of modern Giza. Khufu’s pyramid, known as the Great Pyramid, is the only one of the Seven Wonders of the World that still survives.

Egyptian pyramids served as tombs for kings and queens, but they were also places of ongoing religious activity. After a ruler died, his or her body was carefully treated and wrapped to preserve it as a mummy. According to ancient Egyptian belief, the pyramid, where the mummy was placed, provided a place for the monarch to pass into the afterlife. In temples nearby, priests performed rituals to nourish the dead monarch’s spirit, which was believed to stay with the body after death. In the Old Kingdom (a period of Egyptian history from about 2575 bc to about 2134 bc), Egyptian artists carved hieroglyphs on the walls of the burial chamber, designed to safeguard the dead monarch’s passage into the afterlife. These hieroglyphic writings, which include hymns, magical spells, instructions on how to act in front of the gods, and other pieces of useful knowledge, are known as the Pyramid Texts.

During the Old Kingdom, the Egyptians built their largest and most ambitious pyramids, typically of large stone blocks. Over time, the size and quality of the pyramids decreased, probably because they were extremely costly. In the Middle Kingdom (2040 bc-1640 bc), the Egyptians built pyramids mostly of mud brick. All pyramids were aligned to the cardinal directions, meaning that their sides ran almost exactly due north-south and east-west. Most pyramids rose from desert plateaus on the west bank of the Nile River, behind which the sun set. The Egyptians believed that a dead monarch’s spirit left the body and traveled through the sky with the sun each day. When the sun set in the west, the royal spirits settled into their pyramid tombs to renew themselves.

The internal layout of pyramids changed over time, but the entrance was typically in the center of the north face. From here a passage ran downward, sometimes leveling out, to the king’s burial chamber, which ideally was located directly underneath the pyramid’s center point. Sometimes, in addition to the burial chamber, there were storage chambers within the pyramid. These chambers held objects used in burial rituals as well as items for the deceased to use in the afterlife. Some of these items were valuable, and in later years people robbed many of the pyramids and stole the objects.

A pyramid never stood alone in the desert. Instead, it was the focus of a complex of temples and smaller pyramids. Priests and officials entered a typical pyramid complex through a temple near a harbor connected to the Nile by a system of canals. This so-called valley temple was linked to the pyramid by a long, covered walkway, known as a causeway. The causeway ran up from the valley through the desert to another temple, called a pyramid temple or mortuary temple. This temple was connected to the pyramid at the center of its eastern face.

Most pyramid complexes had satellite pyramids and queens’ pyramids. The satellite pyramids were too small to serve as burial places, and their purpose remains mysterious. They may have contained statues representing the king’s ka, an aspect of his spirit. The queens’ pyramids were simpler, smaller versions of the kings’, sometimes with small temples all their own. They were intended for the burial of a king’s principal wives.

The largest pyramid ever built, King Khufu’s, is often called the Great Pyramid. It lies in the desert west of Giza, accompanied by the pyramids of Khafre and Menkaure (Khufu’s son and grandson). The Great Pyramid was built during Khufu’s reign (2551 bc-2528 bc). Vandals and erosion have stripped away some of the Great Pyramid’s outer material, and some of its uppermost levels have been dismantled, but it still retains its sense of majesty.

Construction

The base of the Great Pyramid forms a nearly perfect square, with only a 19-cm (about 7.5-in) difference between its longest and shortest sides, out of a total length of about 230 m (756 ft). This huge square is also almost exactly level. When newly completed, the Great Pyramid rose 146.7 m (481.4 ft)—nearly 50 stories high. The pyramid’s core probably includes a hill of unexcavated rubble, making it impossible to determine its exact number of blocks. Researchers estimate that 2.3 million blocks were used to build the Great Pyramid, with an average weight of about 2.5 metric tons per block. The largest block weighs as much as 15 metric tons.

The work of quarrying, moving, setting, and sculpting the huge amount of stone used to build the Great Pyramid was most likely accomplished by several thousand skilled workers. Thousands more unskilled laborers and supporting workers—bakers, carpenters, water carriers, and others—were also needed for the project, so that a total of as many as 35,000 men and women were involved in the project. Many archaeologists and engineers now believe that the pyramid builders were not slaves, as was previously thought, but paid laborers who took great pride in their task. Most were probably farmers, contracted to work for a limited period. Specialists, who were permanently employed by the king, filled the positions that required the most skill—architects, masons, metalworkers, and carpenters.

In building Khufu’s pyramid, the architects used techniques developed by earlier pyramid builders. They selected a site at Giza on a relatively flat area of bedrock—not sand—which provided a stable foundation. After carefully surveying the site and laying down the first level of stones, they constructed the Great Pyramid in horizontal levels, one on top of the other.

Most of the stone for the interior of the Great Pyramid was quarried immediately to the south of the construction site. The smooth exterior of the pyramid was made of a fine grade of white limestone that was quarried across the Nile. These exterior blocks had to be carefully cut, transported by river barge to Giza, and dragged up ramps to the construction site. Only a few exterior blocks remain in place at the bottom of the Great Pyramid. During the Middle Ages (5th century to 15th century) people took the rest away for building projects in the city of Cairo.

To ensure that the pyramid remained symmetrical, the exterior casing stones all had to be equal in height and width. Workers marked all the blocks to indicate the angle of the pyramid wall and trimmed the surfaces carefully so that the blocks fit together. During construction the outer surface of the stone was left unfinished; excess stone was removed later.

As the Great Pyramid rose, the workers built large ramps to drag their materials up the sides of the structure. The exact form of these ramps is not known, but scholars believe that they were probably built wrapping around the pyramid as they rose. These ramps were probably made of desert clay mixed with water and bonded with limestone debris left over from the construction work.

When the workers had completed the pyramid and installed the pyramidion, or cap stone, ramps still covered the surface of the pyramid. As the workers dismantled the ramps from the top down, they slowly exposed the pyramid’s stone surface, which stonemasons smoothed and polished. When the ramp was gone, the pyramid was displayed in its full majesty.

Interior

The interior of the Great Pyramid is complex, with a series of passages leading to several rooms. The most important room is the King’s Chamber, the room in which Khufu’s body was placed during his funeral. In this room the priests left items that Khufu, like all Egyptians, would need for the afterlife. Although the builders tried to block passages and doors when they left the pyramid after the king’s funeral, tomb robbers did eventually take everything of value.

The entrance to the Great Pyramid was set 17 m (55 ft) above ground level. It was intended to be used only once, during Khufu’s funeral, when special scaffolding was erected. Once the scaffolding was dismantled, the entrance’s height served as a security measure against tomb robbers. The entrance leads to the Descending Passage, which runs down through the pyramid into bedrock beneath the pyramid and levels out until it reaches the Subterranean Chamber. About 18 m (60 ft) from the pyramid entrance, before entering the bedrock, the Descending Passage intersects another corridor, called the Ascending Passage, now sealed with three large granite blocks.

The Ascending Passage runs upward for about 39 m (129 ft), until it levels out and enters the so-called Queen’s Chamber. Early Arab explorers of the Great Pyramid gave it this name in the mistaken belief that the queen was buried here. Instead, it most probably held a statue of the king that represented his ka, a form of his spirit. The walls of the unfinished Queen’s Chamber grow closer as they rise and meet at a single point at the ceiling. This form results from each level of stones in the walls projecting slightly outward from the level beneath it, an arrangement called corbeling.

Where the Ascending Passage levels off horizontally and runs toward the Queen’s Chamber, it also intersects with one end of the Grand Gallery, a large, corbeled passageway 47 m (153 ft) long and 8.5 m (28 ft) high. The Grand Gallery most probably held some of the large stones that were used to plug passages after the king’s funeral. In the western wall at the point where the Ascending Passage and the Grand Gallery meet, there is an opening to a tunnel that winds its way down through the core of the pyramid and the bedrock to meet the Descending Passage near the Subterranean Chamber. It probably provided air to the workers carving out the Subterranean Chamber.

At the upper end of the Grand Gallery, another level corridor runs south into the King’s Chamber, a simple, rectangular room faced entirely with red granite. All that remains in the room now is a granite sarcophagus in which King Khufu was buried, near the western wall. About 1 m (3 ft) above the floor, near the center of the northern and southern walls of the King’s Chamber, are openings to shafts that run upward through the pyramid to the exterior of the pyramid. The exact purpose of these shafts is not known. Similar shafts lead out from the Queen’s Chamber but are blocked after 65 m (213 ft) and never reach the exterior of the pyramid.

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