Argyrokastro Castle, Medieval castle in Gortynia Municipality, Greece

Argyrokastro Castle is a castle in mountainous Arcadia, near the village of Magouliana, at an elevation of 1,450 m. It is also known as the Gortyniako dynamari, the Gortynian stronghold. It was erected during the Frankish rule by the Villehardouin dynasty of the Principality of Achaea, and served as their summer retreat.

Argyrokastro was built during the Frankish period by the Villehardouin dynasty of the Principality of Achaea, who used it as a summer retreat. The site had earlier held the Arcadian city of Argyrokastro, which disappeared centuries ago. In 1927 Magouliana was briefly renamed Argyrokastro, a name soon dropped.

The castle's alternative name, Gortyniako Dynamari, links it to Gortynia, the Arcadian region where it stands. A further name change touched the nearby village: on 20 August 1927 Magouliana was renamed Argyrokastro, though the name was soon dropped. The castle itself shares its name with an ancient Arcadian city that occupied the site and vanished centuries ago.

To reach the fortress, visitors use a paved road that connects Magouliana with Lasta village. The climb to the site is manageable on foot, and the location is freely accessible without entrance charges.

The Greek name Argyrokastro means "silver castle", and the alternative Gortyniako Dynamari means "Gortynian stronghold". On 20 August 1927 the nearby village of Magouliana was officially renamed Argyrokastro, but the name was soon dropped again.