We have been to Marseille twice.  The first time was an excursion on the 2013 cruise out of the port of Toulon.  The second time was a change to the schedule when our original stop in Monaco was canceled due to bad weather.

The first time was to go to the cathedral(Notre Dame) on the mountain above the city.  The second stop since it was a last minute thing there were no excursions available so we went into the city and just walked all over the downtown area.  It was a happening place and since it is a major seaport with lots of private boats so there was quite a bit was going on.  Great just to walk around and soak up the area.