scale its hard to say, in fact there are four boards, ops sorry! exhibition display, all are same size, around 1mt of diameter.
Each one is a closer view of the previous one, first one is a map of the mediterranean sea and last one is the harbour with the temple.
The one with the temple should be 1/72, the one with many boats is around 12-15mm models, then it's a third one at really far scale (1:2400?) to display how boats navigated always keeping the shore in sight, and the fourth one was a map of the mediterranean sea.
On the website of the museum you can find a virtual tour quite well done, but dont know how these display appear.