The ship heads back to Sydney from Wellington but is due in Auckland on Sunday, December 6.
While it is the sister ship of Voyager of the Seas which has been here for several seasons, it is about 5cm longer.
Explorer will begin a 13-day coast cruise from Auckland after its December 6 visit.
Adam Armstrong, Royal Caribbean commercial manager Australia said his line was growing at 30 per cent to 50 per cent a year.
The biggest cruise ship to enter New Zealand so far is the Queen Mary 2 at 148,528 gross tonnes and 345m in length but Royal Caribbean is bringing what will be an even bigger vessel, Ovation of the Seas, here next summer.
The arrival of the Explorer comes as figures released today show international visitor spending up 38 per cent for the year to the end of September.
International visitors spent $9.4 billion in those 12 months, according to the latest International Visitor Survey released today by the Ministry of Business, Innovation and Employment (MBIE).
Spending by visitors from China was up an estimated 78 per cent from the previous year to $870 million, the United States up 55 per cent to $674 million, Britain up 43 per cent to $720 million. Spending by from Australia was up 23 per cent to $1.9 billion.
Per person spend is up 26 per cent ). The increase in per person spend accounted for 70 per cent of the increase in total spend, with increases in visitor numbers having a lesser effect. International visitor arrivals were up nine per cent for the year end September 2015 compared to 2014.
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