Arrived two days early in Barcelona. Rented Segways for tour of city (highly recommended). We also rented these Segways in Florence and Rome which was a great way to tour many places in a short period of time. Stayed at the highly rated (tripadvisor.com) Casa Camper hotel. Perfect for us due to the 100% non-smoking hotel room policy, a rare thing in Europe. Boarded quickly at noon with a organized group numbering boarding system.
Only worthy disappointment, which was not in our control, was our balcony cabin was right next door to a chain-smoking couple. The smoke actually leaked into our room and the use of the balcony was limited due to the smoke drift. We have been on many cruises, but this was terrible. The hallway even smelled of their smoke for the entire cruise. Requests to "cut back" went unanswered and there was no empty cabins on the ship to move to.
Marseilles: Just walked around town by following a tourist red line path painted for that purpose to visit the sites. Florence: Had private car transport ($350) take us to Pisa and Florence for our Segway tour. Plan accordingly as beach traffic can be an unexpected nightmare on the weekends. Rome: Had crazy private driver (drove 95 MPH) take us into Rome in 1 hour but was late picking up at the ship. Tried to take train from Rome back to ship which was a mistake. Train was delayed due to protesting and we took a last minute cab back to port or we would miss the ship. Regardless of what all other posters say about rail transport, don't do it if you are on a tight timeline. Its not worth the stress. Naples: Took private driver to local attractions. I think Pompeii is boring as it is the same ruins over and over again especially after also visiting Herculean. Advice: Do one or the other. Istanbul: Took private guide. Best port for us. Athens: Arrived on a Sunday which is a good day to be driving in Athens.