Achaea or
Achaia (, , Ἀχαΐα) was (and is) the northernmost region of the
Peloponnese, occupying the coastal strip north of
Arcadia. Its approximate boundaries were to the south the mountain range of
Erymanthus, to the south-east the range of
Cyllene, to the east
Sicyon, and to the west the
Larissos river. Apart from the plain around
Dyme, to the west, Achaea was generally a mountainous region.