Costa Serena is a Concordia-class cruise ship for the Italian cruise line Costa Cruises. The name Serena was intended to symbolize harmony and serenity. Since its inauguration it has been the line's flagship. She entered service in mid-2007. The ship was constructed by Fincantieri in Sestri Ponente. Her sister ship Costa Concordia was launched in 2006. The two ships are the largest and longest ships in the Costa Cruises fleet.