Fort of São João
Azores, Portugal
Fort of São João (Forte de São João), also known as Fort of Biscoitinho (for the lava rock formations along its coastal frontier), is a medieval fort, in the civil parish of São Mateus da Calheta, in the municipality of Angra do Heroísmo, on the Portuguese archipelago of the Azores.
Fort data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).