Past the modern village of Isthmia about 5km and around a headland is Kenchreai, which was explored in underwater searches in 1963 by the University of Chicago and Indiana University, under Robert Scranton.
The south harbor mole can be seen very clearly, extending into the sea.
There is a system of warf houses from the 1st to 5th centuries AD, also partly visible and which continue under the modern road.
At the shore end of the mole are remains of a Christian church with some mosaics and a Sanctuary of Isis, which is mostly underwater.
From here came the glass panels in the museum (the technique known as 'opus sectile') with Nilotic and architectural panoramas, as well as large full length portraits of Homer, Plato and others.
The earthquake of around 375 AD sealed them in the sanctuary, along with the wooden furniture mentioned above, a pulley block, and the bone and ivory decorations.
The northern mole at the other end of the harbor can be reached on foot in a few mintutes. Here are remains of roman structures excavated by the Greek Archaeological service in 1976.