A mastaba is a type of Ancient Egyptian tomb in the form of a flat-roofed, rectangular structure with outward sloping sides that marked the burial site of many eminent Egyptians of Egypt's ancient period. Mastabas were constructed out of mud-bricks or stone.
The greatest stimulus for the ancient Egyptians was their belief in an afterlife. This was reflected in their architecture and most prominently by the enormous amounts of time, money, and manpower involved in the building of their tombs. “Egyptians believed that the soul could live only if the body was preserved from corruption and depredation.” From the predynastic era forward, the ancient Egyptians strove to develop methods for preserving the bodies of the dead. Initially embalming methods were used, and later architectural tombs were devised to preserve the corpse indefinitely. The body would be placed in a deep, sealed chamber such as a Mastaba. Because the remains were not in contact with the dry desert sand, the natural process mummification of the remains could not take place. In order to preserve the remains, the ancient Egyptian priests had to devise a system of artificial mummification. 
The word Mastaba comes from the Arabic word for a stone bench (مسطبة), because when seen from a distance it resembles a bench. Inside the mastaba, a deep chamber was dug into the ground and lined with stone or bricks. The exterior building materials were initially bricks made of sun dried mud which was readily available from the Nile River. Even as more durable materials of stone came into use, the cheaper and easily available mud bricks were used for all but the most important monumental structures.
The above-ground structure was rectangular in shape, had sloping sides, a flat roof, was about four times as long as it was wide, and rose to at least 30 feet in height. The mastaba was built with a north-south orientation. This above ground structure had space for a small offering chapel equipped with a false door to which priests and family members brought food and other offerings for the soul of the deceased. A second hidden chamber called a "serdab" (سرداب), from the Arabic word for “cellar,” housed a statue of the deceased that was hidden within the masonry for its protection. High up the walls of the serdab were small openings. These openings “were not meant for viewing the statue but rather for allowing the fragrance of burning incense, and possibly the spells spoken in rituals, to reach the statue.”
The mastaba was the standard type of tomb in pre-dynastic and early dynastic Egypt for both the pharaoh and the social elite. The ancient Egyptian city of Abydos was the location chosen for many of these early mastabas.
Even after pharaohs began to construct pyramids for their tombs, members of the nobility continued to be buried in mastaba tombs. This is especially evident on the Giza Plateau, where hundreds of mastaba tombs have been constructed alongside the pyramids.
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