The castle of Argos stood on the acropolis of the settlement of the same name. Traces of it may now be seen in the area of the Stavros (Holy Cross) Monastery. The settlement of Argos, held by some sources to have been founded and inhabited by Dorians (Epidaurians or/and Argives) until the 15th century, has disappeared completely. It is thought to have occupied the plain south of the acropolis hillock, in SW Nissyros. The acropolis of Argos apparently dates to the same period as Palaiokastro at Mandraki. It controlled the sea between Nissyros and the neighbouring islands to its SW as well as the volcanic carldera, being within sight of the castles of Emboreio, Nikia and Parlettia. The castle of Argos is one of the five castles mentioned by the Italian traveller and cartographer Christoforo Buondelmonti in 1420