Looming over the medieval city on Guimarães’ hilltop, with its crenellated towers and cylindrical brick chimneys, Paço dos Duques was first built in 1401 and later pompously restored as a presidential residence for Salazar. Today it's open to visitors, who can wander through the rooms, which house a collection of Flemish tapestries, medieval weapons, a chapel with glittering stained-glass windows, and enormous tapestries that relate various episodes in the Portuguese attempt to conquer North Africa.