Princess Cruises has launched its longest cruise itinerary to date, a three and a half-month voyage that covers the distance of about 1.5 times the circumference of the Earth.

Set to launch in 2018, the 106-night journey will visit 40 destinations in 27 countries including new ports-of-call like Greenland, Newfoundland in Eastern Canada, as well as overnight stays in New York, Barcelona and Venice.

All told, the Sea Princess will cover 32,000 nautical miles in a circumnavigation of the globe that's equal to about 1.5 times the distance around the Earth.

The title of the longest world tour in 2017, however, goes to Oceania Cruises and their “Around the World in 180 Days” voyage aboard the Insignia.

Departing from Miami, the six-month voyage riffs off the classic French novel by Jules Verne, “Around the World in Eighty Days” and takes guests to the Caribbean, Hawaii, French Polynesia, Australia, New Zealand, Hong Kong, Singapore, Mumbai, Egypt, Israel, Rome, Barcelona, Lisbon, France and Canada before returning to Miami.

Meanwhile, for those who aren't the seafaring type, Crystal Cruises has expanded from sea to sky with the addition of a Boeing 777-200LR jet to their fleet of cruise ships, and the company is launching, in partnership with The Peninsula hotel brand, a round-the-world tour that takes guests to 10 cities over 27 days, under the name Crystal AirCruises.

Sea Princess's 106-night cruise departs from Sydney, Australia and is priced at US$21,999 per person.