During the ancient times Kyllini was the most important port in West Peloponnisos and the main gate of Ancient Ylida, the city of the Olympic Games.

The Ancient god Hermes was the protector of the city with an amazing statue representing a phallus on a stand, a symbol of prosperity. Also in ancient Kyllini were sanctuaries of Asklipious and Aphrodites.

The Franks, at about 1204 step-up the port of Killini and created Glarentza, a new city in the place of Ancient Kyllini. From 1220 to 1223 they build the Chlemoutsi Castle. With the new port as a strong base and the mighty castle the city developed strongly and became very famous during the middle ages. The city exported plum, oil, wine and cotton.

Then next stage in Kyllini’s history was the 1428 when Konstantinos Palaiologos became the master of the city. In 1432 the port of Kyllini destroyed in order to avoid the pirates. This was the beginning of decadence ant through years the city transformed into a small settlement.

When Greece liberated from Turks the economy of Killini was based in agriculture, stock-raising and fishery. Throug the years, the connection with Eptanissa and with the main railroad network improved the city’s economy.

Today, the municipality of Kastro Kyllini has four municipal departments. The Castro has 857 residents, The Kato Panagia has 1266 residents, the Neochori has 1323 residents and the Kyllini has 952 residents.