Ancient Calendar
Between 500-200 BC, in the Casma Valley, Peru, the thirteen towers of the Chankillo Archaeoastronomical Complex told time. The row of teeth-like protrusions formed a solar observatory marking the solstices, the equinoxes, and every other date within the year with a precision of 1-2 days.
https://www.google.com/search?client=safari&sca\_esv=3d5aec0ebbda9031&hl=en-ca&q=chankillo&sa=X&ved=2ahUKEwiZ4I6KvbOFAxUCLtAFHR1dCagQ7xYoAHoECAkQAg&biw=1214&bih=785&dpr=2
Photo: Juancupi, CC BY-SA 4.0
https://commons.wikimedia.org/wiki/File:Las\_trece\_torres\_del\_observatorio\_astron%C3%B3mico\_de\_Chanquillo.jpg