Ring of Brodgar
Links:
https://minds.wisconsin.edu/bitstream/handle/1793/64662/Kasten_Megan_Thesis.pdf?sequence=1
https://en.wikipedia.org/wiki/Ring_of_Brodgar#cite_note-Hedges-15
https://www.visitscotland.com/de-de/info/see-do/ring-of-brodgar-p669061