On Sunday, the 704-passenger Adonia cruise ship is expected to sail from Miami, Florida, to Havana, Cuba. In doing so, the vessel is sailing into history — becoming the first U.S. leisure ship to voyage between the United States and Cuba in more than 50 years.
The ship pulled out of the Port of Miami around 4pm ET, accompanied by a large contingent of police in the water and the Coast Guard in the air.
The Adonia is part of Carnival's Fathom brand, based around so called "impact travel" where passengers not only take part in the usual cruise activities like eating, drinking and sun-bathing, but have the opportunity to learn from and work with locals in each port of call.
Passengers "will have free time and be able to go on your own a bit, so I'm not sure it will feel that different" from a full fledged leisure cruise, Carnival CEO Arnold Donald told CNBC in an on-board interview. He said the cruise was completely sold out, and there were about a dozen Cuban-born passengers on board.
Those factors are what makes this legal. American's still cannot legally visit Cuba as tourists, but they can if they qualify for one of 12 categories, including "people-to-people" and "cultural exchange" programs offered under Fathom's umbrella.
As protesters rode along the side of the ship, passengers lined the upper decks waving American and Cuban flags. Donald and Fathom president Tara Russell gave a short speech to the passengers, thanking the crew and employees that made the cruise happen.
"We're delighted to be here," said Donald. "We're humbled, it's an honor, it's a privilege."
Other Carnival brands will be travelling to Cuba over time as port space becomes available, he said.