Hi poormom..it was Ascension Day when we were in Marseilles so most of shops were not open but we did take the shuttle to the Old Port and explored on our own. The market was very interesting with the fishmongers handling their fresh catch....we noted a defined share of labor...the men had caught the fish so the women did the gutting and cleaning....hmmm
We walked to Fort Saint Jean and enjoyed that but as the weather was a little iffy we did not spend a lot of time there. People had booked ship tours to Aix and Provence and sounded very happy with them. Also in Marseilles is the basilica Notre-Dame-de-la-Garde. It is on the highest point in town but not within walking distance but a tour of Marseilles offered it.
Have fun, wear good walking shoes and sunblock.