The temple complexes at Karnak and Luxor, on the east bank of the Nile near ancient Thebes, together formed the ceremonial heart of Egyptian state religion for well over a thousand years, expanded and rebuilt by successive pharaohs who each added their own monuments, obelisks, and inscriptions to what became the largest religious building complex of the ancient world.
Karnak was dedicated chiefly to Amun, who was fused with the sun god Ra into the composite deity Amun-Ra during the New Kingdom, elevating him to the head of the Egyptian pantheon and making Karnak's priesthood one of the most powerful religious and economic institutions in Egypt, at times rivaling the pharaoh's own authority. An avenue of sphinxes once connected Karnak to the nearby Luxor Temple, used for the annual Opet Festival, in which the cult statue of Amun was carried in procession between the two sites to renew the connection between the god, the pharaoh, and the Nile's fertility cycle on which Egyptian civilization depended. The temples functioned as working religious institutions rather than static monuments, housing priesthoods, temple economies built on land and labor dedicated to the god's service, and daily ritual cycles of offering and purification conducted largely out of public view within the temple's inner sanctuaries. Much of what is known about New Kingdom era Egyptian religious practice, including hymns to Amun-Ra and detailed temple ritual texts, survives through inscriptions carved into these temple walls, making Karnak and Luxor primary sources in their own right rather than only architectural remains.