5 reasons Royal Caribbean's 9-month Ultimate World Cruise is unlike most around-the-world cruises

• TikTok is enthralled by Royal Caribbean's nine-month Ultimate World Cruise.
• Other cruise operators run world cruises, some annually.
• But few have gained the traction of Royal Caribbean's — and these are the five reasons why.

TikTok can't get enough of Royal Caribbean's ongoing Ultimate World Cruise, and for good reason: There's been nothing like it before.

World cruises may have just entered the spotlight, but the concept of a global sailing is nothing new with some cruise lines even operating one annually.

However, few have gained the social media traction and attention as Royal Caribbean's nine-month itinerary has. These are the five reasons this could be the case.

1. At 274 nights long, Royal Caribbean's itinerary is over double the length of most world cruises.

Most of these cruises sail for about three-and-a-half to five months (or six if it's Oceania's).

In 2024, ultra-luxury Regent Seven Seas Cruises announced its longest global itinerary yet: 154 nights in 2026 starting at $95,000 per person. But even this extended sailing is dwarfed by Royal Caribbean's nine-month vacation, which set sail from Miami on December 10, 2023.

If all goes to plan, Royal Caribbean says its Ultimate World Cruise won't conclude until September 10, traveling to more than 150 destinations in 65 countries along the way.

2. The ship is planning to sail to all seven continents.

Despite its name, not all world cruises plan to sail to all seven continents. Royal Caribbean's does, including traversing the infamous Drake Passage to Antarctica.

However, the ship isn't scheduled to stop at many ports in Africa, save for Egypt and Morocco.

Travelers interested in an extended Africa cruise could try premium cruise line Oceania's two-month Africa and Asia itinerary instead.

3. Smaller premium operators are behind most of the popular world cruises.

Both Princess Cruises and MSC Cruises have 116-day world cruises scheduled for 2025. However, not every family-friendly mass market operator hosts these around-the-world trips.

Instead, some of the most popular globetrotting cruises are run by premium and luxury cruise lines, often annually. This includes Royal Caribbean Group's luxury Silversea. In 2025, the high-end company's world cruise would sail from Tokyo to New York over four months, starting at $81,900 per person.

Crystal, Viking, and Azamara also offer these monthslong cruises, many of which have sold out. Just don't expect them to be as affordable as MSC's $13,200 itinerary.

4. The ship is bigger than most of ships that operate world cruises.

Royal Caribbean selected the 965-foot-long Serenade of the Seas as the 13-deck floating home for its nine-month cruise.

The 20-year-old ship was previously refreshed in 2022 following a $29 million 2012 refurbishment. At 1,073 staterooms and a 2,476-guest capacity, the Serenade of the Seas is much smaller than some of Royal Caribbean's ships, including the new world's largest Icon of the Seas.

But as is commonplace for the cruise line, Royal Caribbean's Serenade of the Seas is larger than the vessels used for most other world cruises. However, it's worth noting many of these competing companies are already known for having smaller ships.

Silversea's 2025 and 2026 world cruises would be aboard the almost 700-foot-long, 596-guest Silver Dawn. Oceania often taps its 594-foot-long, 684-guest Insignia for its annual sailings. That's the same guest capacity as Azamara's Onward, which embarked on the operator's first world cruise itinerary on January 5 and is scheduled to be used again in its 2025 and 2026 global itineraries.

However, MSC's Magnifica — enlisted for its 2023, 2025, and 2026 global sailing — is only two feet shorter than the Serenade of the Seas, although it can accommodate more than 3,000 guests.

5. Royal Caribbean is still selling unusually short segments of the itinerary.

Nine months at sea could be difficult for even the most dedicated cruise fans. To make the itinerary more accessible, travelers could have reserved one of its four segments ranging from 63 to 87 nights. The last two — "Middle East and Mediterranean" and "Europe and Beyond" — of Royal Caribbean's world cruise can still be booked.

Segmenting a world cruise is common. However, Royal Caribbean has taken this a step further by selling shorter itineraries, ranging from nine to 29 nights, within these four legs.