Of course the Gateway of the Sun in Tiahuanaco also belongs to the 'twin' monuments. The opening through which sun is going to enter must be related in some way to the holes in GD24. Perhaps it is so easy as the hole in the gateway being the same hole as in GD24? Notably GD24 never is found in double-shape. But then, why the variant without holes?

If we go back to the beginning, then presumably the 'origin' was the heliacal rising of the Pleiades. That marked the beginning of the year (= half-year). Due to the precession of the equinoxes this beginning of the year slowly moved the seasons. On the seafloor of Bimini are signs that the Pleiades were used to mark the beginning of the year already before the heliacal rising of the Pleiades had reached spring equinox. Near the equator it doesn't matter so much if spring equinox and the heliacal rising of the Pleiades do not coincide.

The perspective of half-years is important. That means we should initially have only two double staffs, one at the beginning and one at the end of the half-years. Four staffs would be enough to mark the 'earth'.

When Odysseus made a wooden spear and thrust it into the eye of the cyclops that was a description for reaching the end of a half-year (a cyclop).

The wooden spear has two ends, and the other end would point at the beginning of the same half-year. One such spear is like a diameter enclosing half a circle. The letter π (or better Π) indicates the phenomenon of the ratio between this half-circle and its diameter.