MS Allure of the Seas is a cruise ship owned and operated by Royal Caribbean International. Together with her sister ship, Oasis of the Seas, she holds the record for the largest passenger ship ever constructed, although the Allure is 50 millimetres (2.0 in) longer than the Oasis, making her technically the largest despite the fact that both ships have identical superstructures,Designed under the name "Project Genesis", she was ordered from Aker Finnyards in February 2006 and her construction began at the Perno shipyard in Turku, Finland, in February 2008. She was named in May 2008 after a contest was held to name her and her sister. The keel of the Allure of the Seas was laid on 2 December 2008, shortly after the shipyard had been acquired by STX Europe.