Digging up a monument

Salgada settlement (Rio de Moinhos, Borba, Central Alentejo).
Around 3000 BC.

Complex ditch and, at least, two enclosing walls: one of them, has been found on last year excavation (2, 50 m large) and a second one (on the first two images) has just been found this week (1, 20 m large).
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