Yes, we have spent time in Civitavecchia. There are a number of shops and a great street market. There are some lovely coffee shops along the sea front.
To find the market - when you walk out of the port gates cross over the road, you will see a Macdonalds, walk up that road and then take the first left and then first (or could be 2nd) right, walk up hill a bit and you will see the market. I hope my memory serves me right.
We love this port but bear in mind if you get there on a Sunday most things will be closed.
Thank you Finn. That's very helpful.
You could also try the next seaside port along the coast - Santa Marinella. Just 5 minutes on the train or a short bus/taxi ride. Typical seaside port with nice beach.
Not a lot, the market is well worth a visit otherwise just take a walk along the sea front and enjoy a drink, You could go to Rome on the train as the station is quite convenient and it takes about an hour, you could go in and have a quick look around but be sure to be back in Port in time to catch the ship. otherwise enjoy the ship for the day whilst the majority of passengers are slogging around Rome on tours .