The Rio Castle in opposition to its counterpart, the Castle of Rumelia at Antirrio, 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.
The castle was built by the Ottoman Sultan Bayezid II in 1499 above the ruins of an ancient temple of Poseidon, within three months. Along with its twin, the Antirrio Castle, they were intended to protect the entrance to the Corinthian Gulf, and were nicknamed the 'Little Dardanelles'. The castle is located on the sea shore, with its northern side protected by the sea and the southern by a broad moat, filled with sea water, and two outer bastions (ravelins), linked to the main fort by stone bridges. It has two gates, the central one, facing landwards, and the sea gate.
In 1533, it was briefly captured by the Genoese under Andrea Doria, but the Ottomans recaptured it later in the year. In 1687, during the Morean War, it was taken by the Venetians under Francesco Morosini. The Venetians rebuilt the castle, restoring and strengthening it by the addition of towers, giving it its final shape. The Venetians also added the small chapel of the Life-giving Spring. The Ottomans retook it in 1715, and remained until they surrendered it to French General Nicolas Joseph Maison. Between 1831 and 1912, the castle was used as a military and then civilian prison, whose inmates were often used by the municipality of Patras for cleaning the streets of Rio.
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.