Public transportation between Punta Cana and Sosua/Cabarete would work as follows:
1. Take a cab to get to the Expreso Bávaro bus station in Verón (Punta Cana). (You will see from the timetable below that there are only 6 buses a day from Verón to Santo Domingo, there are more buses from Higüey than from Verón/Punta Cana so if there is no suitable Expreso Bávaro bus from Verón then Cocotours would have to drive you from Punta Cana airport all the way to the Expreso Higüey bus station in the town of Higüey, a 45-minute drive from Punta Cana airport.
2. Ride the Expreso Bávaro bus from Verón to Santo Domingo. The Expreso Bávaro buses tend to be new and clean, their new buses have reclinable seat backs, and an on board toilet, but there is not much legroom, and for most of the ride Hollywood movies are shown on flat screens attached to the ceiling, with the Spanish soundtrack blaring out of speakers throughout the bus. Maybe a good idea to bring earplugs if you don't want to listen to the movie which may feature such sounds of gunshots, car chases and police sirens etc. The Expreso Bávaro buses also have an on board ticket collector who will walk up the aisle shortly after departure to collect your ticket, or your fare since it is possible to board the bus without a ticket and pay onboard. The Expreso Bávaro buses arrive at the bus terminus on Juan Sánchez Ramírez street in Santo Domingo. The Expreso Higüey buses terminate at the bus station at Parque Enriquillo in Santo Domingo.
3. Take a cab across Santo Domingo from the Expreso Bávaro bus terminus to the Metro Bus station. An alternative would be to take a Caribe Tours bus from the Caribe Tours bus station in Santo Domingo to Puerto Plata, however generally the Caribe Tours buses make more stops en route. Metro and Caribe Tours buses are airconditioned, and always have toilets onboard. A short stop is normally made in Santiago (or la Vega) en route where there are additional toilets and cafeterias where food can be purchased for consumption onboard.
4.Ride the Metro Bus (or Caribe Tours bus) from Santo Domingo to Sosua The journey takes about 4.5 hours.
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It is quite the adventure and almost like taking the trip you just took by air all over again on the ground as far as the length of time goes and certainly is a lot more of a hassle. Of course your arrival time will dictate if it is possible to make this trip in one day or if you need to spend the night somewhere along the way. Once you get on Metro or Caribe buses, you are on your way to Sosua. We have a neighbor who plays gigs in Punta Cana. He says he can drive from Punta Cana to Cabarete in around 6 to 6.5 hours and he does not use a helicopter. Some of our guests have rented cars, but then they were returning them to Punta Cana at the end of their trips when returning home.