Foz do Rio Frio dolmen
Ortiga, Portugal
The Anta da Foz do Rio Frio is a megalithic tomb, or dolmen, situated in Ortiga in the Mação municipality of the Santarém District of Portugal. Also known as the Anta da Casa dos Mouros, it dates back to about 3500–4000 BCE during the Middle-to-Late Neolithic period. It is the only one of the many such dolmens in the municipality that is still standing, having been identified in the early 1970s and excavated in 1982. Several artifacts have been found at the site.
Monument data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).