MS Mariella is a cruiseferry delivered in 1985 to SF Line and has since operated as a part of Viking Line. She was built by the Wärtsilä Shipyard in Turku, Finland. Her sister ship is the Olympia (now MS Princess Anastasia). Mariella was the worlds largest cruiseferry for a short while in 1989 before MS Athena.
http://virtualglobetrotting.com/map/viking-lines-ship-mariella/