Dr. Steinhauer, Ephor of the Second Ephorate of Prehistoric and Classical Antiquities, also extended permission for us to electronically survey the shipshed remains inside the basement of the modern building. This was accomplished with a Total-station and the Reflectorless Electronic Distance Measurement system (REDM). We expanded this accurate survey to include the submerged architectural remains preserved in the harbour basin. In addition, sections were drawn of the colonnades, ramps, and walls preserved in the basement.

In Area 1 evidence was found of substantial remains of the superstructure, ramps and side-passages under the present sea level, which will add significantly to the understanding of the architecture and function of the Zea shipsheds. The electronic survey of these structures demonstrates that they line up with the shipshed remains surveyed on land. In Area 2 we found remains of several well preserved shipsheds.

During the Peloponnesian War the entrances of the three harbours of the Piraeus were fortified towards the sea. This was done with fortified quays that ended in towers which made it possible to close off the harbour entrance with a chain, the so called limani kleistos – the closable harbour. In Area 3 remains of the south-eastern fortified quay is build into the modern quay, and the underwater survey determined that remains of this quay and other structures probably related to the harbour fortifications are preserved in the sea. Next to the fortified quay we discovered, yet another shipshed, which is probably the last building in the south-eastern part of the shipshed complex before the fortified harbour entrance.