MS Mariner of the Seas is one of five Voyager-class cruise ships from Royal Caribbean International; nine biggest amongst cruise ships. Its total length is 1,020 ft. (311 m) with a beam of 161 ft. and a max capacity of 3,807 passengers.
MSC Fantasia is the tenth largest cruise ship in the world and the biggest ever operated by MSC Cruises. It has a max passenger capacity of 3,900 besides crew. Its length is 1,092.5 ft. (333.3 m) with a beam of 124.4 ft. (37.92 m).