I visited Marseille with my wife and two friends in April 2007. We had planned to visit Aix-en-Provence and had obtained the bus and train timetables in advance. There is a regular bus service between the towns.
However, cruise ships dock a few miles from the rail and bus stations in Marseille so realistically, you must use the ship's shuttle bus or take a taxi to and from the City Centre. This adds to the cost
There are plenty of taxis at the Cruise Terminal and upon arrival, we found that for a party of four, it was very cost effective to take a taxi all the way to Aix. Our driver charged 55 euros each way (including tip) and he picked us up at the appointed time to take us back to the ship.
The arrangement had the advantage that we were able to stay much longer in Aix. Furthermore, the motorway between Marseille and Aix is susceptible to congestion - and the public bus can suffer serious delays. Our driver took a diversion on the outward journey, which avoided the jam.
The train route between Marseille and Aix is actually quite good and there are about 2 trains an hour with a journey time of 30 - 40 min each way. These are "TER" or regional trains and perhaps you had problems finding these trains on some of the search engines (such as RailEurope). The two cities are actually about 20 miles apart, and its also an easy drive (about 25 min). French taxis are very expensive and you are probably looking at 150 Euros (or more) for a taxi round trip. Another option is to simply rent a car which would allow you to drive to Aix, and perhaps also to Arles and even Avignon. Train station is 3.5 miles west of Aix. You can take a bus into town for 4-5E each way. Train trip is 35 minutes long and would eliminate the traffic concerns. However, I would highly recommend renting a car and driving. Provence is absolutely gorgeous and worth exploring. There are so many wonderful towns (St Remy and Les Baux) From the port the nearest carhire places are Europcar and Hertz.
I would suggest you adjust your spelling from Aux to Aix-en-Provence and then look at the following sites
Regards. ... Neil.
I have posted the answer several times but the fascists that run this board seem to have blocked my answer...lets see if that gets though!