The Port of Cienfuegos is scheduled for a major expansion, reports AP. Venezuela and Cuba are building a refinery and petrochemical hub around the southern port city, and that’s boosting cargo traffic.

The port will add three berths and a terminal for supertankers within four years, says AP. Cienfuegos currently has five berths. Supplying the refinery with Venezuelan crude oil, supertankers have docked at Cienfuegos since 2008.

Yet the entrance to Cienfuegos Bay is a major bottleneck for supertankers. Tugboats are operating at the limits of maneuverability in the straight passage.

“The Port of Cienfuegos will be an industrial port. This will be its main role,” Luís Medina, general director of the national ports authority, told journalists. He said petrochemical products are changing the nature of the port. Cienfuegos is not the only port expansion in Cuba. Construction of a $300 million container terminal at the Port of Mariel, just west of Havana, began early this year, with funding from Brazil and Dubai. Mariel will also be the base for offshore oil operations.