Nothing prepares you for the Great Hypostyle Hall. Step inside and you stand among 134 sandstone columns arranged in sixteen rows, packed so densely that sightlines vanish and sunlight falls in narrow, dust-flecked shafts. The twelve central columns rise some twenty-four meters — the height of an eight-story building — their tops flaring into vast bell-shaped capitals carved as open papyrus blossoms. The remaining 122 columns, slightly shorter, are capped with closed papyrus buds. The whole hall was conceived as a petrified marsh, the primeval reed-swamp from which the Egyptians believed the world first rose. Covering roughly five thousand square meters, it remains the largest room of any religious building anywhere on Earth. Most of it was raised under Seti I and his son Ramesses II in the nineteenth dynasty, and the architraves spanning the columns are reckoned to weigh some seventy tons apiece — lifted, by best guess, up long ramps of mud and rubble.

Karnak's chief deity was Amun, and his name itself meant "the hidden one." Long the local god of Thebes, Amun rose with the city until, fused with the sun god as Amun-Re, he became the supreme power in the Egyptian pantheon. The earliest trace of him here is a modest eight-sided column from the eleventh dynasty. Everything else grew around that seed. When Thebes became the capital in the eighteenth dynasty, nearly every pharaoh felt obliged to leave a mark. Hatshepsut, one of the few women ever to rule as king, raised twin obelisks that were the tallest in the world at the time; one still stands, the second-tallest ancient obelisk left upright anywhere. The priesthood of Amun grew so wealthy and powerful on the temple's vast estates that it eventually rivaled the throne itself — a concentration of sacred influence almost without parallel in the ancient world.

One pharaoh tried to break Amun's grip, and Karnak still bears the scar. Amenhotep IV, who renamed himself Akhenaten, abandoned the old gods in favor of the sun-disk Aten and built a new temple just east of the main complex. Then he moved his entire court and capital away from Thebes altogether. It was a direct challenge to the priesthood that had come to control Egypt's religious life. The moment he died, that priesthood took its revenge. Akhenaten's temple was demolished so thoroughly that its full plan is still unknown, its very stones broken up and recycled into other walls, and the records of his reign were hunted down and effaced. Standing at Karnak, you are looking at the winning side of a culture war fought across the thirteen-hundreds BC — and at the lengths the victors went to make a king disappear.

Karnak was never a single sanctuary but a cluster of precincts. The largest belongs to Amun-Re; others, mostly closed to visitors, honor the mother goddess Mut and the war god Montu. In Mut's precinct, archaeologists found a "porch of drunkenness" built by Hatshepsut for the Festival of Drunkenness, where priestesses and ordinary people drank deliberately to excess in honor of a goddess who, in myth, was talked out of destroying humanity only when tricked into drinking beer dyed red to look like blood. Centuries later, after Rome closed the pagan temples, Christians moved into the ruins and founded churches among the columns; in the central hall of Thutmose III's festival temple you can still make out painted saints and Coptic inscriptions over the older Egyptian carving. Few places on Earth hold so many layers of belief in one footprint of ground.