The ship was great. The accommodation, food, service and entertainment was very good.
On the down side:
1. To get from one end of the ship to the other you had to pass smokers areas no matter which way you went. We found this most annoying and something that should be corrected. As they only make up a minority of passengers, put them in a closed off area and they can effect only their own lungs.
2. If you have a debit card, don't tell them. Instead arrange to pay cash. If you have a card, each time you spend money (drinks, excursions etc) they will have that amount set aside in your account so that you cannot use it. At the end of the cruise Costa then debits your card for the total amount, but in fact this is debiting the card twice! After four weeks the daily deductions are cancelled and the money becomes available to you once again. In our case, this was near the end of our holiday and with $600 missing from our account, it made the end of our holiday less enjoyable because of the need to be so frugal. (some hotels do the same with the cost of accommodation).
2. The daily newsletter. The translation from Italian doesn't explain all of the misinformation but some of it. For example, Turkey became independent from Russia in 1975. They were also bombed in the 1850's. Rarely did the newsletter indicate where we were passing such as the Dardenelles which is of importance to Australians, New Zealanders, the British and Indians because of the Gallipoli campaign in World War One.
We also visited Constanza in Romania. Don't bother. It looks like everything has gone downhill since Nicolae Ceausescu was executed and that's saying something!. In the Ukraine, the ports of Odessa and Yalta were real eye openers. Beautiful country, lovely cities and parks and very friendly. Lots of history such as the Crimea Conference of 1945 between Roosevelt, Churchill and Stalin in the Lividia Palace of Tzar Nicholas II which you could visit.