ORCHOMENUS, an ancient city of Arcadia, stood in a plain surrounded by hills which separated its territory from that of Mantinea on the S., and those of Pheneus and Stymphalus on the N. Its founder is said to have been Orchomenus, the son of Lycaon. Its situation, in the midst of a well-watered valley, and its acropolis, upon a high and impregnable hill, seem to have rendered it in early times a very important city. Homer calls it "rich in flocks;" and several of its kings are said to have spread their rule over all Arcadia. But during the Peloponnesian war, when its acropolis had probably fallen into ruins, and when its last king, Pisistratus, had been murdered by an oligarchical faction, Orchomenus began to decline. About 367 B.C. three of its tributary towns were depopulated to furnish inhabitants to the newly-founded city of Megalopolis; in 313 B.C. it was taken by the Macedonian general Cassander; and ever afterwards it continued to be bandied about between different belligerent powers. Yet, in the time of Pausanias, Orchomenus was still inhabited, and at the present day its ruins are seen near the village of Kalpaki.