Old Navarino Castle
Municipality of Pylos-Nestor, Greece
The Old Navarino castle is a 13th-century Frankish fortress near Pylos, Greece. It is one of two castles guarding the bay on which it sits; the other is the Ottoman-built New Navarino. It is frequently known simply as Palaiokastro or Paliokastro ("old castle"). It occupies the site of the Athenian fort at the 425 BC Battle of Pylos.
Fort data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).