First of all, thanks for the good photographies that were communicated.
I want to give some informations about those strange constructions you've come across ithe gersian landscape.
First of all, they're gallo-roman.
Second, they were build on funerary purposes, in honor of a man or a family. The y have or have had a niche to put a statue in.
Third, the average height was more than 10 meters
And finally, most of them have been used as quarries : there isn't so much stone in the area...
Regards
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