In general terms, these walls are among the best preserved of any of the Hellenistic period and show a high level of skill and finish. There is clear evidence of quarrying immediately south of the southeast tower of the citadel. Based on the design of the defense towers, Ober proposes that the site was fortified after 370 BCE. Lawrence opts for a date in the late 4th century BCE, on the assumption that Demetrios Poliorcetes built the fortress rather than simply occupying it. The site was under the control of the Achaean League in 243-224 BCE, and in 224 - 146 BCE it joined the Boeotian League. Shrines of Melampos and Heracles are known to have existed by inscriptions recovered on the site. The town and its warehouses operated down into Roman times. An inscription of c. 420 CE listed Aigosthena as a free city. A five-aisled Christian basilica was erected in the lower fortified area in the medieval period, and there was a monastery complex within the citadel. The modern village Aigosthena, also known as "Porto Germeno", is part of the municipal unit of Vilia. Its permanent population was 80 at the 2011 census. It is a popular beach resort with a small port.