Paleokastro means 'old castle'. The castle was built by the Frankish ruler Nicholas II de St. Omer after 1278. He married the widow of William Villehardouin, who conquered the Peloponnese after the crusade to Constantinople. This castle was dominating the sea and the bay and offered a great view over a big part of Messinia. It is even stated that on clear moonless night, the light reflection of Malta can be seen. Later on, Venetians engineers redesigned the castle. The walls to west and south were the most impressive ones. The steep slopes of the Koryphasion horst to east and north formed a natural protection. The main entrance was from the south. The main harbour was probably also at the south of Koryphasion. This castle didn't cover the main entrance of the bay. Therefore, an extra castle was needed: Neokastro.