Royal Caribbean has been offering short cruises on its massive Oasis-class ships for some time, first on Allure of the Seas. It even launched a brand-new ship (Utopia of the Seas) directly into short sailings last year, and is set to start offering 3- and 4-night cruises on its popular Wonder of the Seas in the Fall.

"These ships clearly represent the next generation of Fun ships," according to the company. "They will be experiences unto themselves."

Royal Caribbean will still be able to claim this even the cruise lines do not seem to be trying for this crown anymore.