In ancient Egyptian history, the Old Kingdom is the period spanning 2700–2200 BC. It is also known as the "Age of the Pyramids" or the "Age of the Pyramid Builders", as it encompasses the reigns of the great pyramid-builders of the Fourth Dynasty, such as King Sneferu, who perfected the art of pyramid-building, and the kings Khufu, Khafre and Menkaure, who constructed the pyramids at Giza. Egypt attained its first sustained peak of civilization during the Old Kingdom, the first of three so-called "Kingdom" periods (followed by the Middle Kingdom and New Kingdom), which mark the high points of civilization in the lower Nile Valley.
The concept of an "Old Kingdom" as one of three "golden ages" was coined in 1845 by the German Egyptologist Baron von Bunsen, and its definition would evolve significantly throughout the 19th and the 20th centuries. Not only was the last king of the Early Dynastic Period related to the first two kings of the Old Kingdom, but the "capital", the royal residence, remained at Ineb-Hedj, the Ancient Egyptian name for Memphis. The basic justification for a separation between the two periods is the revolutionary change in architecture accompanied by the effects on Egyptian society and the economy of large-scale building projects.
The Old Kingdom is most commonly regarded as the period from the Third Dynasty to the Sixth Dynasty (2686–2181 BC). Information from the Fourth to the Sixth Dynasties of Egypt is scarce, and historians regard the history of the era as literally "written in stone" and largely architectural in that it is through the monuments and their inscriptions that scholars have been able to construct a history. Egyptologists also include the Memphite Seventh and Eighth Dynasties in the Old Kingdom as a continuation of the administration, centralized at Memphis. While the Old Kingdom was a period of internal security and prosperity, it was followed by a period of disunity and relative cultural decline referred to by Egyptologists as the First Intermediate Period.