They're called floating cities for a reason, and the billion dollar 'Ovation of the Seas' is the world's fourth-largest cruise ship and the biggest ever to visit New Zealand.
"The ship's 168,000 gross tonnes, we hold 4900 guests, we have 1600 crew, we do 25-30,000 meals a day," said Royal Caribbean International hotel director Michael Rasmussen.
It's too big to dock in Auckland, but a dozen tenders ply the route from ship to shore, ferrying hundreds of tourists an hour to grateful businesses.
"The first thing they say about New Zealand is how beautiful it is," said Mr Rasmussen.
"The weather's crisp, the mountains are beautiful, the people are friendly. That's the first thing that comes to mind and I know that because I'm outside listening to them as they come back.
A report by Market Economics on behalf of NZ Cruise estimated the benefits this year at $419 million, but that's more than four times Statistics New Zealand's calculation.
"Things like airfares are not included, for example, in the Stats NZ," said Mr Rasmussen.
"There's a calculation done on car data that's different, there are so many measures on crew spend not included, for example, and no New Zealand passengers on cruise ships are included.:
Cruise New Zealand head Kevin O'Sullivan says cruise ships are a money spinner, whatever the stats.
"We will be working with Stats New Zealand and all the players in the new year to come up with numbers we're all happy with," he said.
In Auckland, the economic boost could be greater still and the council is keen to cash in.
Ships like the 'Ovation of the Seas' are only going to get bigger, so to help them dock, Auckland Council has agreed to build a concrete pillar 85 metres out called the 'dolphin'.
It will enable huge ships, like the 'Ovation of the Seas' and others, to dock alongside The Cloud on Queens Wharf.
Ahead of that, Royal Caribbean's given a vote of confidence to New Zealand - it's doubling port visits here this season.