One can take a ferry from Cienfuegos across the Bahia de Cienfuegos to the Castillo de Jagua opposite.
The ferry point is near Av 46, between Calle 25 and Calle 27. The first ferry of the day departs at 11am. The 8am and another one in the afternoon have been cancelled. Check out the time beforehand from the wall.
As the ferry is for locals, the price is actually 1 Cuban Peso. Hand over the 1 Cuban Peso coin confidently.
The thing is I had no problems with the conductor. But a fellow German tourist was made to pay US$0.50. I am not sure if all foreigners will be forced to pay a 'foreigner's price'. Did the conductor think I was a local Cuban Chinese? Or did he not pester me because I seemed to know the 'true price'?
Anyway, the view across the bay is really pretty.
Once on the other side, the Castillo is moderately interesting. Costs US$1 to enter. The village around the Castillo near the bay is a rather nice place to walk around.
I happened to walk all the way to the 'new town' and received an ugly view of blocks of apartments. At the bottom, goats were tethered to rusty metal rods!