Each year at Thebes, the great cult image of Amun left its sanctuary at Karnak and travelled in procession, carried in a sacred barque along a specially built processional way and, in periods when the Nile flood permitted, also by river, to the temple of Luxor a short distance to the south, accompanied by his consort Mut and their son Khonsu, together forming the Theban triad whose divine family relationship was itself part of what the festival annually reaffirmed.
The god remained at Luxor for a stay of some weeks, its exact length varying across the centuries the festival is attested, before returning in a second procession to Karnak, and the whole cycle, later Egyptian evidence suggests, grew considerably in length, duration and elaboration from the earlier New Kingdom through into the Ptolemaic period, reflecting the festival's continuing central importance to Theban religious life across an enormous span of time. The pharaoh's presence at the rites, whether personally or through his officiating priests, was central to the festival's meaning, and reliefs at Luxor temple depicting the so called divine birth of the king, in which Amun is shown as the king's true divine father, are closely associated with Opet ritual space, tying the festival directly to the theological basis of pharaonic legitimacy.