When the Great Pyramid at Giza was built, the north pole star was Thuban, in the constellation of Draco, the dragon, the constellation which never sinks below the horizon (“the impersihable ones”), Thuban perfectly aligned to the star shaft from the King’s Chamber circa 2200 b.c. And because the Great Pyramid is, amazingly to typically (on this) ignorant egyptologists, perfectly aligned to true north, the Egyptians clearly were aware of precession, which is the slow clockwise wobble of the earth’s axis, therefore pointing to progressively new pole stars around a celestial circle tracing though Draco.
You can’t know true north without timekeeping, why longitude must be measured by arc seconds and arc minutes, according to solar time, so how’d the Egyptians do it way back in old kingdom times, with sun dials? Hardly. They did it (‘though not acknowledged by most egyptologists) by measuring that precession rate, 72 years/degree, then applying hexagon geometry to the circle of the earth, quite simple really, explained in article #2 at http://IceAgeCivilizations.com.
See too http://genesisveracityfoundation.com.