There's a mound builder site near Saint Louis where they used that exact method. There is a central observation point then posts laid in circles around it. Some of the posts align perfectly with the solstices others with planting times.
Even without the sticks in the ground most people who spend a lot of time outdoors would notice the pattern of the sun shifting across the sky and daylight changes.
Lower_Departure_8485 t1_ja9s7a6 wrote
Reply to comment by Anarchaeologist in Eli5: How did people know how long a year was in olden times? by Slokkkk
There's a mound builder site near Saint Louis where they used that exact method. There is a central observation point then posts laid in circles around it. Some of the posts align perfectly with the solstices others with planting times.
Even without the sticks in the ground most people who spend a lot of time outdoors would notice the pattern of the sun shifting across the sky and daylight changes.