The photo above illustrates the curious optical phenomena that appears on the pyramid without its casing, at dawn and sunset at the time of the equinoxes (around 21 March and 22 Sept), a shadow appears on the south face of the great pyramid, apparently dividing it in half, with the shaded side nearest the sun.
This poses some more interesting questions regarding our ancient past.. How did a civilization that was supposedly 'not as advanced' as us build these by-hand and with such precision to create this concavity that is only seen from the air and on the equinoxes? Not all is what it seems and our ancient history may be very different from what the elite-controlled mainstream will acknowledge.
The purpose for the concavity of the Great Pyramids remains a mystery and no satisfactory explanation for this feature has been offered. The indentation is so slight that any practical function is difficult to imagine unless that is its exact function was to highlight the day of the equinoxes.
Ancient Knowledge Pt.3 Pyramids, Monuments & Megaliths, Ley Lines (Earth's Energy Grid)