Aigosthena () was an ancient Greek fortified port city of Megaris, northwest of the ancient city of Megara to which it belonged. It is also the name of the coastal settlement at the foot of the ancient city walls, also known as Porto Germeno. The ancient citadel which stands at the foot of Mt Cithaeron and extends down to the sea at the inlet of Aigosthena, on the east side of the Gulf of Corinth, is famous for retaining several of the tallest surviving towers of ancient Greece. Geography Aigosthena is situated on the Alkyonides Gulf, a bay of the Gulf of Corinth. It is surrounded by forested mountains: the Cithaeron to the north and the Pateras to the south. Aigosthena was historically the northernmost city of the Megaris (Megarida). It is 10 km west of Vilia, 20 km southwest of Thebes northwest of Athens. Ancient Aigosthena The ancient site of Aigosthena consisted of a fortified citadel connected to the sea by two fortification walls; the fortress consisting of the acropolis citadel and the lower town. The acropolis stands on a low hill, 450m from the sea. Measuring roughly 90 by 187 m (~575 Doric feet), the citadel was roughly trapezoidal in plan, with the narrower side (113m) facing west toward the sea. The citadel was constructed along the contours of a 55 m hill, and was defended by eight artillery towers incorporated into its perimeter wall. There was a primary gate on the west side into the area between the north and south walls to the sea. A small postern (auxiliary) gate was located immediately north of the second tower on the eastern side. The northern of the two walls to the sea is well preserved, stretching 370 m to a final tower of which the foundations and fallen blocks are now underwater. The northern wall consisted of six towers and a fortified gate running in a nearly straight line from the northwest corner of the citadel to the sea. The bed of a river runs along the probably line of the south wall, which is not evident. The walls were built in a variety of masonry styles, which may be evidence of different phases of construction. Masonry styles in use include isodomic (ashlars with hammered faces and drafted corners), pseudo-isodomic, and - in sections – a style approaching polygonal. In general terms, these walls are among the best