Soterioupolis
Turkey · built 1929
Soterioupolis ("City of the Saviour") or Soteropolis was a Byzantine fortress in the southeastern Black Sea coast during the 10th–12th centuries. The name has been suggested to apply to two different localities, Pitsunda in Abkhazia and Borçka in Turkey.
Fort data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).