Nimes Airport to Marseille
How can I get to Marseille from Nimes airport?
Other than hiring a car I would suggest taking the train. Depending on what train you take you might have a transfer in Avignon. The travel time is a little over an hour to and hour and a half. You will need to take the shuttle into Nimes, it stops at the station or a taxi. The cost of a taxi is about 25€ and the shuttle 5€.
If you do take the train no need to make a reservation, you can buy your tickets the day you travel.