The No. 1 operator of cruises to Cuba reported last week that phone inquiries had doubled since new U.S. regulations regarding travel to Cuba were issued two weeks ago, and 50% of the calls were coming from U.S. citizens.

Website traffic has tripled, said Dugald Wells, president and CEO of Calgary, Alberta-based Cuba Cruise.

Wells said that immediately following the surprise announcement of a thaw in U.S.-Cuba relations, Cuba Cruise also saw an uptick in bookings from residents of Canada, its top market.

“In some part, we attribute that to people saying, ‘I want to see Cuba before it changes,’” Wells said.

Cuba Cruise is in its second season of sailings around Cuba, using the 35-year-old Louis Cristal, a ship it chartered from Cyprus-based Louis Cruises. The Cristal carries some 960 passengers at double occupancy. It is currently running about 60% capacity, which Wells described as “break-even territory in our second year of operations. Obviously we’d love to sail full.”

(At least one other cruise operator, Star Clippers, offers sailings from Cuba, but a  spokeswoman did not respond to a request for comment.)

Cuba Cruise has a jump on numerous U.S.-based cruise companies that have to varying degrees expressed interest in sailing to Cuba, but until the U.S. government-imposed embargo is lifted, those lines have no immediate plans to start going there.

In a recent forum for travel agents on the Freedom of the Seas, Michael Bayley, president of Royal Caribbean International, said, “Obviously, the latest announcement about the liberalization of relations is of interest to us.”

But speed bumps lie ahead.

Bayley said Royal has a team studying the possibilities, but most of the ports in Cuba are incapable of handling ships of the size of the Freedom of the Seas. The one exception, he said, is Havana, but that port has serious infrastructure issues.

“At the moment, there’s effectively been no change for our industry,” said Bayley who estimated it might be three to five years before major cruise companies go to Cuba.

Operators of smaller ships are somewhat more optimistic. Edie Rodriguez, president of Crystal Cruises, said that if conditions were right, it would be relatively easy to add a port call in Cuba.

“We’re able to switch itineraries very quickly,” Rodriguez said. “We’ll just swap out a port.”

But like other cruise executives, Rodriguez said the Cuban infrastructure was an obstacle. “The roads are so bad you’d have to go very slowly,” she said. “Our guests would not be happy about that.”

Wells agreed that the infrastructure lags. “Cristal is the biggest ship we can safely maneuver into and out of these ports we go to,” he said. “So we’re kind of limited in our future growth by the infrastructure.”

But some facilities are good, including a terminal in Havana that was upgraded for Pullmantur before the Spanish line was acquired by Royal Caribbean Cruises Ltd. and stopped sailing into Cuba.

And all the terminals in Cuba are well located, Wells said.

“These passenger terminals may be dated and frayed, but they’re right in the middle of town,” Wells said. “You walk off the ship and cross the road and you’re in that postcard with the cobblestone streets and the old American cars and the big churches. It’s fantastic.”

Currently, fewer than 5% of the passengers sailing with Cuba Cruise are U.S. citizens. Those who are come through two tour operators, Road Scholar and Insight Cuba, which have Treasury-approved people-to-people programs in one of 12 travel categories, such as education or athletics.

Previously, such trips involved detailed documentation, reporting and approval from Treasury officials. Now, under general licenses, there is less paperwork required.

“It’s much less onerous than it was, but you still need to be part of a group that is under the auspices of a [company] that operates such tours,” Wells said.

Cuba Cruise does offer a way to book directly through its website. However, after booking, travelers must register with the nonprofit Fund for Reconciliation and Development and receive back a participant letter of authorized travel. The cost is $75.

For agent bookings, Cuba Cruise has been paying 12% commission, but it is increasing that to 15% for the balance of its season through mid-March. It pays 8% on shore excursions.

Wells said he expected to be competitive even if Cuba opens to larger cruise companies.

“We’re focused on the destination,” he said. “We’re going into smaller ports. Our entertainment program is 90% Cuban and a couple of Canadian acrobats from Cirque du Soleil. We’re really working hard to present a program that is an authentic, somewhat in-depth exploration of Cuba as a destination.”