Cuba is relatively well connected by bus
You will be able to visit all major cities and travel all around the country by bus. While there are a few bus companies there, as far as I know, only Viazul is the one that takes tourists traveling independently.
Go to the bus station at least an hour before departure
While Viazul has a site with a current service schedule, it is not possible to book tickets online. You must go to the bus station ahead of time and queue for a ticket. Since buses are not that frequent, they tend to sell out quick. But, there’s an option…
Shared taxis are also a good option
Taxi drivers stand in front of the bus station to pick the excess of passengers without tickets. They offer a shared taxi ride to some of the most popular and well-connected cities in Cuba for about the same price of the bus and faster. If you’re going to a smaller town not covered by the shared taxi, you can take the shared taxi to the closest city possible, and from there take a local shared taxi called “Almendrones.”
Should they price the shared taxi ride much higher than the bus, then, you’ll need to haggle. Oh, and don’t be surprised if the local sharing your ride paid a fraction of what you paid. That’s Cuba. Foreigners almost always have to pay more than locals.
Local buses cost 1 CUP (about $0.04 – which you can pay in CUP or give 5 cents of a CUC). It is hard to understand the routes, but your host could tell you which one’s you should take to go to most of the important places. Taxis are not expensive, costing about 5 CUC from Old to Central Havana.
Vintage taxis have a set route
All those pretty vintage taxis you see in pictures, those are exclusive for tourists to ride (not drive) and they only go through a select route in Havana. You could, though, have the luck of riding a vintage car as your shared taxi from once city to the other.
Havana is big, but if you have a few days there, you can save money on transportation by walking it and seeing things at a slower pace. I do recommend walking; that’s when you see the best scenes of the city. Prepare to sweat… I mean, sweat crazily!
Also, Viñales, Trinidad, and other popular cities can be walked easily.