The Rio Castle (Greek: κάστρο του Ρίου or Καστέλι της Πάτρας) is located at the north tip of the Rio peninsula in Achaea, Greece, at the entrance of the Corinthian Gulf. The Rio-Antirio Bridge is located next to it, and the local ferry docks lie on either side. Today it is used for cultural purposes, especially concerts and is a tourist attraction.