An hour from Santo Domingo, Baní is the mango capital of the country and the only place in it with sand dunes.
You meet the local guides and stop first for the big native iguanas that live in the area. Then the dunes themselves, the only ones in the Dominican Republic, with sandboarding for anyone who wants it.
On the way out of the national park there is a stop for the mangrove species, and then the salt flats, where salt is still worked by hand. Lunch is Dominican, and the day ends snorkelling off an empty beach with clear water.