Traveling has never been so comfortable. A journey is not just a transfer from one place to another, but it is an experience. For this reason nothing is left to chance. 
A driver will be waiting for you outside the Cruise ship, to make sure you can avoid any inconvenience. After comfortably passed the checks you will see him waiting with a sign with your name written on top so you can easily recognize him. 
At this point he will take care of you and your personal effects, you will just have to sit in a luxury mercedes vehicle, where you will find a bottle of water and a map of Rome, and you can start dreaming and making question. 
From this moment on, Rome is in your hands and if you choose the tour option, the driver will stop in front of all the iconic places of the city and will explain some little anecdote and a bit of history to hear you no longer a foreigner but a local friend.