Ancient Keyhole shape - click on image for larger picture.
Below are images from the Tombs in Saudi Arabia
Ancient tombs of Japan
Below the megalithic tombs of Kofun
Various Keyhole shape artifacts and depictions
Tanit Goddess Keyhole
Various depictions of the goddess Tanit - showing Keyhole shape.
Various depictions of the Keyhole shape
A variety from different sources depicting this Keyhole shape - plus collages showing connections.