In the town of Viseu, we walked narrow streets of small black and white pavers to Cathedral Square, where there is a church and a cathedral facing one another. Here is the home of the Grao Vasco Museum, dedicated to one of the best Portuguese painters of the 16th century.These buildings are striking because their architecture is so dramatic, accented blacks and whites and very distinct shapes in the turrets and crenellations of the high building. Next to a big city square, beautiful tiles decorate a wall beneath a city street. When do you see blue tiles on a public street? In Viseu, of course.