In the Kalpaki site, near the ancient Orchomenos, and on a low hill, remains of a medieval fortification are preserved in a dilapidated state.
It is the last medieval fortress to be found in the east in the area of Mainalos which was the successor of the acropolis and the fortification of the ancient Orchomenos and this is very natural due to its strategic position.
Today, a small tower measuring 7x10 m and 2-4 m high stands out at the top of the hill, built on a rock. In its construction, building materials from the archaic fortifications have been used. An underground tank runs along the entire base of the tower. It is possible that it was used by the Byzantines and the Franks for defensive purposes. Next to the tower to the east are the ruins of another smaller building covered with holly trees. On the east and north side of the tower there are traces of wall foundations which seem to have protected the tower. Although the tower does not have visual contact with any of the other castles in the area, it seems that its position controlled the roads to Corinth and Argolis via Candila and Achaia.
Source: UNIVERSITY OF PATRAS
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