A mastaba (/ˈmæstəbə/, /ˈmɑːstɑːbɑː/ or /mɑːˈstɑːbɑː/) or "pr-djt" (meaning "house for eternity" or "eternal house" in Ancient Egyptian), is a type of ancient Egyptian tomb in the form of a flat-roofed, rectangular structure with outward sloping sides, constructed out of mud-bricks (from the Nile River) or stone. Mastabas marked the burial sites of many eminent Egyptians during Egypt's Early Dynastic Period and Old Kingdom.