Again just returned from Ocean Village Cruise. We were told there was nothing there really and effectively there are a few bars and shops (touristy). However, there is a train service, don't know how reliable but others did use it. If you get off the boat sharpish and get the first one out you will get back to the ship in time.
There is also a car hire business just at the port - last week was 35 euros a day for a Corsa. Suggest this would be the best option for Olympia is not far away and get a map from the hire firm.