It's the largest privately own residential yacht on the seas.
While not the biggest cruise ship on the oceans, it is certainly the most luxurious.
And what sets it apart is that its passengers are a residential community who live on board as it travels the world.
The passengers hail from 19 countries, including the US and Switzerland, and the floating paradise includes 165 private residences.
The ship boasts 12 decks, the only full-sized tennis court at sea, a cinema, fitness centre and a luxury spa.
Private on-board apartments have their own library and wine collection and residents are invited to watch the sunset beneath the starry sky of whatever part the globe they happen to be in at that time.
The World is currently sailing around the British Isles and dropped anchor in Belfast yesterday morning for a two-day stay. It will then sail to Londonderry and Galway.
The Belfast Telegraph spoke to visitors as they disembarked to a warm welcome from Lord Mayor Mairtin O'Muilleoir.
Tatiana Haimo, a 22-year-old from California, recently graduated from university where she studied linguistics.
So, despite the lure of staying on board, passengers were keen to get off and explore. She was heading towards the north coast.
Sarah Graham, a marketing assistant with Visit Belfast, was a travel adviser to occupants of the ship.
Nancy Callahan, who lives and works in Maui in Hawaii, travelled here on The World with her brother Denis.
"The ocean view on board is quite different from that of the ocean view property in Hawaii," she said.
Nancy described her stay as ultra-comfortable, but after being at sea, she said was nice to roam around on land.
"Life on board is everything you would expect and more. It was great, but now it's going to be nice to be able to explore on land," she said.
Her brother, Denis Callahan, is in his mid-fifties and lives mainly in Ohio, where he is an attorney.
While both Norway and Scotland appealed, Denis said "visiting Ireland was top of the list".
He has had a keen interest in the history of Northern Ireland and was looking to find out more about Belfast.
Like Tatiana, Fred and his family boarded the ship in Norway. This is the first time his family has visited Northern Ireland but said "the journey was great and we're excited to be here".
This ship docked in Belfast in 2002, its inaugural year.
Mr O'Muilleoir said it was great to see the vessel coming to Belfast as "it's a city on the rise", and credited entrepreneur Martin Naughton for attracting ships like The World to Northern Ireland.