Teichus or Teichos (Ancient Greek: Τεῖχος), also known as Teichus/Teichos of the Dymaeans (Ancient Greek: Τεῖχος Δυμαίων, romanized: Teichos Dymaion) or Kalogria Castle, was a prehistoric acropolis (fortified settlement) in the territory of Dyme, in ancient Achaea, Greece, near the promontory Araxus, which was said to have been built by Heracles, when he made war upon the Eleans.

It was taken by the Eleans under Euripides in the Social War in 220 BCE, but it was recovered by Philip V of Macedon and restored to the Dymaeans in the following year.

[2][3] The fortress stands in a strategic position on a rocky hilltop, north of the Prokopos lagoon, near the village of Araxos.

During the war between the Achaean and the Aetolian Leagues (220–217 BC) it was seized by king Philip V of Macedon.

During World War II it was used by occupying Italian forces, who built a number of military installations on the site and damaged the prehistoric fortifications.