Santo Domingo to Santiago.
andres said:
Sorry. I mean from the airport in Santo Domingo to the autopista heading north.
The highway you take Westbound as you leave the airport area takes you straight to Santiago.
The problem is that the way they designed the road through Santo Domingo, you might find yourself on an elevated portion of the thruway that heads you off to the downtown core and land up having to fight your way back to the main highway. You will have to drive slow and pay attention to the signs, of which there are few.
Other than the part through Santo domingo, the rest will be easy.