Black and White, plus blue

Piazza dei MiracoliNIKON D40X (200mm, f/5.6, 1/400 sec, ISO100)

While observing this particular of the Duomo di Pisa (in the same Cathedral Square where it’s located the famous Leaning Tower), I saw that itĀ  looks like a B/W photo, but with an intenseĀ  blue coming from the clear sky. I was fascinated by this tonality mix.