The Turkish-Venetian fort at Rhion forms together with the modern bridge Río-Antírrio (Europe’s longest cable bridge!) one of the most important places of interest in Achaia. The fort is open to visitors from 8.00-15.00 hour). It was built by the Turkish general Bayezid II in just 3 months in 1499. Because of its strategic position the fort formed the stage for several battles between the Venetians and the Turks. The original Turkish fort consisted of a large triangle, with an enormous entrance gate with two towers in the southern wall and a small castle for its garrison in the north. The western wall may have been demolished by the Venetians during their occupation of the site. The entrance gate is nowadays used as a chapel. The fort was taken in 1532 by Andrea Doria, an Italian admiral in the service of the Genuese. In 1603 the Maltese Knights severely damaged the fort.
In 1687 the fort was again taken by the Venetians, who used it to control the Peloponnese. They undertook heavy modifications to the fort, adapting it to “modern” warfare by building two large bastions to the north and west side of the fort, while building two lozenge-shaped bastions at the southern and southeastern ends. Finally, two triangular bastions were built in the waterfilled  fosse.
Little now remains of the original buildings on the inside. Some roman-christian marble fragments lie in front of the old stockrooms.