Asopos was an ancient city of Lakonia. The founding period of the Asopos city is vague and may be placed in prehistoric times before the descent of the Dorians. The city made great progress during the Roman era to the early Byzantine period. Asopos was a member of the “Commune of Free Lakonians”, had a safe harbor and its own currency with the inscription ASOPEITON.
On the one side the coin depicted the gods Poseidon, Artemis and Nemesis while on the other side was the inscription “ASOPEITON”. In another version of the coin, on the one side god Dionysus was depicted and on the other side god Poseidon with the inscription “ASOPEITON”. Such a coin is kept in the Archaeological Museum of Sparta. The city sank at 365 B.C. after a powerful earthquake. In Plytra which is situated in the municipality of Monemvasia,in the administrative district of Lakonia and particularly in the region “Red” ,the ruins of the sunk city are detected, even today, into the sea and along the shore.
In the 19th century the valley of Asopos stretches between the mountain range of Parnon and the Laconic bay covering an area of 80.000 roods. In statistical charts of 1828 the Monemvasia province listed a total of 26.500 olive trees and counted 55 olive mills.