The shipments include items from authorized religious and charitable groups and from people shipping packages to family and friends on the island.
They leave from a Miami River terminal through a weekly service provided by International Port Corp. The company holds licenses from the U.S. Treasury Department's Office of Foreign Assets Control, which enforces the 50-year-old economic embargo on Cuba, and from the U.S. Commerce Department.
The service costs about $6 per pound and takes one to two weeks depending on the destination in Cuba.
Similar service already exists from other U.S. ports. But this is the first time in decades that such a shipment arrived from Miami, which is home to a large Cuban exile community.
The first ship from Miami, the Ana Cecilia, entered Havana Harbor just as the sun began to rise Friday.
The few people who were on the seaside Malecon avenue at that hour were unaware of its arrival or had only heard about it through word-of-mouth. Cuban media have not mentioned the renewed shipping lane.
Wilfredo O'Farril, who was reading a newspaper, mistakenly thought it had arrived days ago even though the Ana Cecilia floated right by him minutes before.
"It's not in the press. I heard about it from other people. They said it arrived the day before yesterday, I think, a yacht or a ship with aid," O'Farril said. "Some packages from people in Miami that were authorized to send them to Cuba. We hope this continues, for the benefit of the people."
Another man fishing along the seawall was unimpressed.
"I have been fishing off the Malecon for the past 12 years," Daniel Herbert said. "I don't think the appearance of a new flag on the waters of Havana Harbor is going to change my lifestyle."