The site was discovered in 1969, in rescue excavations carried out by E. Mastrokostas and S. Marinatos on behalf of the Greek Archaeological Service. Unfortunately, the site attracted less attention, in comparison with the rich cemeteries excavated at about the same time at Tsepi and Vranas by Marinatos. The Plasi excavation and its finds were never thoroughly studied nor fully published. The available information is limited, deriving solely from short preliminary reports, published in Greek journals.

These first investigations brought to light a fortification wall of either EH or MH date, a MH large building complex, the Μegaron of Plasi, a MH pottery kiln, the Perivolos of an Archaic Sanctuary, all depicted in the plan by Ι. Travlos in 1988. Graves and pottery of various periods, indicate the continuous habitation of the place, from the Neolithic to the Early Byzantine Period.

Since 2014, the Department of Archaeology and History of Art of the National and Kapodistrian University of Athens has been conducting a new series of systematic excavations, in order to clarify important issues left unanswered by past research, and to uncover fully the remains of the various periods.