At the southern entrance of Navarino Bay, the fortress of Niokastro or Neo Navarino, as it was named in contrast to Paleokastro, on the other side of the bay, dominates. It was built by the Ottomans in 1573 after their defeat in the naval battle of Nafpaktos, for effective control of one of the most important trade sea routes between East and West and is one of the best preserved castles in Greece.