Tiny town with nothing special to offer, or at least not so when I was there in '96. But it's cozy and people are very hospitable and not used to tourists. It's right on the main highway between La Habana and Piņar del Rio in the north, and it's greatest claim to fame is probably that Federico Garcia Lorca is supposed to have written one of his poems in the plaza de armas here.
Favourite spots:
Ehm...the mango garden where I lived and strolling the streets of the village. And there was this lovely little old lady selling homemade cookies and sweetened mango sodas for next to nothing - one of the few who'd let gringos shop with pesos cubanos.
What's really great:
The fact that there was no such touristification as one sees in i.e central Havana, where everything for sale to everyone. There was a cosy old lady sitting by the road selling homemade cookies and sodas for 2 pesos, nothing but that.
Sights:
There aren't really any... But the village is pretty and surrounded by banana plantations and orange fields.
They do have a local "Caimito Museum", but not very well upkept, and certainly not interesting unless you read Spanish.
Accommodations:
Staid in a communist indoctrination camp (Campamento Internacional Julio Antonio Mella), staff is absolutely hilarious and they rent available room to backpackers, or at least did so at the time, for a couple of dollars. Quite basic though, with 8 bunk beds to the room and shared bathrooms - water and electricity on and off a bit, and you'd always chase frogs (and once a snake) out of the bathroom before entering.
Other recommendations:
There is an excellent and almost deserted beach nearby, Playa El Salado. 11 kilometers, or about twenty minutes by bus/car from the town. Also La Habana is only 34 kilometers down the road.
There are a few small tiendas in town, as well as two banks and a small clinic.