The town of Blaye itself is well worth a visit with its imposing citadel which was designed by Vauban around 1685 . A UNESCO world heritage site, it is open every day of the week throughout the year. Guided tours are very worthwhile and splendid panoramic views can be had from the walkway on the top of the walls. Here is where you can take a ferry across the estuary to the wine area of the Medoc where there are plenty of chateaux to taste and buy wine .