Dymaean Wall, Prehistoric fortress in West Achaea, Greece.

The Dymaean Wall, also called the Castle of Kalogria, is a prehistoric acropolis on the Araxos cape in West Achaia, about 35 km from Patras. Its cyclopean circuit runs roughly 200 m long, 10 m high and 5 m thick, built of massive blocks; the Russian sources give a length near 250 m, a width of 4.5–5.5 m and a surviving height of 8.4 m.

Built in the late Neolithic period, the wall remained in use until the Venetian era. Around 220 BC it was taken by the Eleans under the general Euripidas and retaken by the Dymaeans with help from Philip V of Macedon. In 1943 Italian and German occupation forces demolished part of the walls to open a passage for vehicles and built machine-gun posts.

The structure displays early Greek military architecture through its cyclopean walls made of massive stone blocks fitted without mortar. This building technique was typical of ancient Aegean fortifications.

Sturdy footwear is essential due to the hilly terrain and uneven paths between the ruins. Visiting early in the day provides better light for exploring the walls and avoids midday heat.

Italian forces during World War II built military installations at this ancient site and modified the prehistoric structures. These external interventions left visible traces in the old walls.