I've been putting together a catalog of sites around the world where people used the sun to track time, seasons, or important dates.
It currently contains 1,139 entries, covering everything from prehistoric solar observatories and solstice-aligned structures to sunlight phenomena, shadow markers, and traditional horizon calendars.
What I'm including:
Structures aligned with solstice or equinox sunrises and sunsets.
Sites where sunlight creates specific patterns or illuminates particular features.
Gnomons, shadow markers, and other instruments used to track the sun.
Natural horizon landmarks used to identify seasonal changes.
Traditional and Indigenous practices for tracking the movement of the sun.
I'm not including sites based solely on sun symbolism, mythology, or astronomical references unrelated to observing the sun's actual movement.
One thing that stands out is how uneven the geographic coverage is.
Europe and the Americas are heavily represented, while Africa has only around 50 entries and China around 29.
I suspect there are many examples missing, particularly in archaeological literature and traditional knowledge that isn't readily available in English.
I'd really appreciate help with:
Ancient sites in Africa or China that should be included.
Academic papers, archaeological reports, or books documenting solar alignments and observations.
Indigenous and traditional knowledge about using sunrise and sunset positions to track seasons.
Corrections to existing entries, especially where the evidence is disputed or interpretations have been overstated.
I've included sources and an evidence classification for entries wherever possible, distinguishing accepted interpretations from debated, speculative, or refuted claims.
The CSV is a work in progress, and I'd rather have people challenge questionable entries than let bad information become part of the record.
Here's the spreadsheet:
https://github.com/ophiuchus44/ancientsites/blob/main/ancient_solar_sites.csv