Near Araxos in the Municipality of Larissos, one can find the most important Mycenaean Acropolis in Western Greece. According to mythology the Wall of Dymaioi was built by semigod Hercules for the protection of the Dymaia Land (Olenos, Tefthea, Larisa, Thelpousa, Faistos and other settlements)
from the incursions of the people of Heleia.

The Dymean Wall or Kalogria Castle was a prehistoric acropolis in Achaea.
The wall was built around the Neolithic period and remained in use until the Venetian rule. It was used once again in 1943 during World War II and tear down a part for opening an entrance for cars. It is located 35 km west-southwest of Patras in cape Araxos in the Mavros Oros in the area of modern day municipality of Larissos.
It was named the Wall of Dyme which it was founded in the Dymean country and Kalogria Castle (different name) from its beach which is nearby. The castle walls which was circular, it had a length of 200 m, 10 m tall and 5 m in width.
According to Greek mythology, the wall was built by Hercules which he battled the Eleans with Augeas and used as an attack. The wall was in a bank location which battled its residents for the hegemony of the area and administered a part of the centre[3]. The wall was used as an attack between the Dymeans and Eleans and around 220 BC, it was ended by the Eleans and general Euripides for taking back Dyme with the help of Philip V Macedon
The wall survives today and for sometimes used for restoration.

Source: http://el.wikipedia.org
Photos: www.tdpeae.gr