Tour Trolleys are available in the Vieux Port area. They will take you through the town of Marseilles, past the old forts and up to the Notre Dame de la Guarde Cathedral. The guides are informative and make their presentation in both French and English.
we spent a three day weekend in marseille spending most of the time doing the flaneur, eating out and wandering freely and enjoyably. marseille is a fascinating old city and we have travelled extensively independantly so we were 'taking all sensibe precautions'...except one:
ALWAYS KEEP YOUR CAR LOCKED EVEN WHEN THERE ARE THREE ADULTS IN IT AT 3.30P ON A SUNDAY AFTERNOON!!!! we were helping a friend locate a hostel and while he rushed in to check availabilty two young guys (on a scooter) attacked us in the car. Firstly they pulled up behind and fortunately one of us (a big guy) noticed the attacker sneaking alongside the side of the four door car. when the attacker opened the rear passenger door he went to attack one of us in the back (22yr old female) - luckily big guy was ready for him and a tussle began - the attacker was pushed out of the door and then quick as a flash opened my front passenger door, grabbed me around the throat and stole my handbag (fortunately not passport!) he took off on the motorbike and that was that. we chased him on foot calling for help from the passer bys (men) who did nothing - one of us speaks fluent french by the way. women in a neighbouring apartment tried to help and call police and said this type of attack had got worse and worse since 'le crise'. we then went to the police station and filed a report which you would need to get insurance and you would also need a french speaker. as one of us can speak french the police were able to understand and very helpful sympathetic.
after this we went to drive out aix-en-provence for the night and the gps was incorrect due to roadworks so we wound up in an every shadier part of the city with people trying to get us to wind down windows etc and pointing *** at you etc as night fell - we crashed a red light to get the hell out of there....
so in short i would go to marseille again because marseille is what it is and it probably always has been however no amount of 'just take reasonable precautions' will do - you need to take extra care here and be on guard at all times - even for a few seconds - the french hotel owner in aix said this is now really common and often women are punched in the face or badly beaten (probably the red tourist number plates don't help) and whenever he goes to marseille, ANYTIME OF DAY OR NIGHT, he always keeps his car locked when he is in it or obviously when away from it.
the silver lining. we have travelled throughout europe, independantly with eurodrive cars, 3 times now and I wouldn't say we thought we were bullet proof but having eaten humble pie and come out reasonably unscathed I would say if you haven't been mugged you have simply been lucky and a place like Marseille is no place to be thinking you are bullet proof - even if you are french and live there.
so if you are a true adventurer you will go anyway, leaving a bit to providence and i fully intend to return on this basis - however don't glibly post 'take reasonable precautions and you will be okay' - you may not be - i say take extra precautions and be extra vigilant!