first published in March 2018
In 1973, Alexander Thom found the Crucuno rectangle to have been “accurately placed east and west” by its megalithic builders, and “built round a rectangle 30 MY [megalithic yards] by 40 MY” and that “only at the latitude of Crucuno could the diagonals of a 3, 4, 5 rectangle indicate at both solstices the azimuth of the sun rising and setting when it appears to rest on the horizon.” In a recent article I found metrology was used between the Crucuno dolmen (within Crucuno) and the rectangle in the east to count 47 lunar months, since this closely approximates 4 eclipse years (of 346.62 days) which is the shortest eclipse prediction period available to early astronomers.
Figure 1 Two key features of Crucuno’s Rectangle
About 1.22 miles northwest lie the alignments sometimes called Erdeven, on the present D781 before the hamlet Kerzerho – after which hamlet they were named by Archaeology. These stone rows are a major complex monument but here we consider only the section beside the road to the east. Unlike the Le Manec Kermario and Kerlestan alignments which start north of Carnac, Erdevan’s alignments are, like the Crucuno rectangle accurately placed east and west.
Figure 2 Two stones, angled to the diagonal of a 3-4-5 triangle 235 feet from north west stone and setting sun at summer solstice