Asea took part in the foundation of Megalopolis, to which city most of its inhabitants removed in 371 BCE;[1] but Asea continued to exist as an independent state, since the Aseatae are mentioned, along with the Megalopolitae, Tegeatae, and Pallantieis, as joining Epaminondas before the Battle of Mantineia in 362 BCE.
The two rivers united their streams, and, after flowing in one channel for 20 stadia, disappeared beneath the earth; the Alpheius rising again at Pagae, and the Eurotas at Belemina in Laconia.
North of Asea, on the road to Pallantium, and on the summit of Mount Boreium, was a temple of Athena Soteira and Poseidon, said to have been founded by Odysseus on his return from Troy.
Ancient Asea occupied a hilltop site and is believed to have been settled by the late Early Helladic period.
The lack of evidence later than the late MH period could result from abandonment of the site at that time or just from natural erosion.