Vryokastro is a prehistoric fortified settlement, the oldest that has been detected in Tinos.
The shells that have been found in excavations, indicate that the area has been inhabited since the Early Bronze Age (3000-2300 BC).
In the Middle Cycladic (or Middle Bronze Age 2300-1600 BC) the settlement is best organized and fortified. The ruins of the walls of the fortress, at the hilltop, are still visible.
After the collapse of the palatial centers of the Minoan civilization, the settlement was gradually abandoned.
Hardly any systematic excavations have ever been carried out since the last decades.