The Great Boat of Khufu: The 'Black Box' to the Construction of the Pyramids
Perhaps this is not the first time that the reader will have heard of how in 1954 the Great Boat of Khufu was discovered, practically intact, at the southern face of the Kheops Pyramid, and how it is believed by the majority to have had cultic significance, although opinions vary within scientific circles. One belief was that the Sun sailed in such a vessel during the day, crossing over to another during the night hours.
Source: ancient-origins.net