European Cruise? Anyone ever go?

Dear Brides,

Has anyone ever been on a European cruise to Italy, Spain, France, etc.?

I'm wondering if there are things to see just off the ship or do you need to book a tour for every port.  

We are celebrating my fiances bday on NCL's Epic Ship.  The excursions all seem to be super expensive.   Any help would be greatly appreciated!

Thanks!
Kim