Palazzo della Civiltà del Lavoro in Rome

You're standing at the Palazzo della Civiltà Italiana, in Rome's EUR district. Locals simply call it the Colosseo Quadrato, the Square Colosseum. One look at the façade and you'll see why. Go on, count the arches. Each side has six rows of nine, all exactly the same. There's a popular story that this is no accident. Benito has six letters, Mussolini has nine.