[CondorFlight]

Wait until you see where the light goes at the solstice; and then paint a picture to fit the light.

Thereafter, you can use that as your calendar.

There are LOTS of “calendar” circles painted in the Southwest, where the light strikes the center of concentric rings on the longest day of the year.

[WayneS]

Okay. But does the rock stay the same for all eternity? And how did the ancients get their paint to last so long?

[JRandomFreeper]

Wait until you see where the light goes at the solstice; and then paint a picture to fit the light.

That's exactly what I did. Wait until the computer said it was winter solstice, and go make a mark on my front porch at sunrise.

Yeah, it's cheating, so what?

/johnny