Flow.

Flow of Water: Rome is a city of flowing water. Fountains send water soaring upward into the sky, creating artificial illumination through the reflections in the flying droplets. But these are just the most obvious segment of water's many travels through the city. Water also seeps from hidden cracks in walls, inching its ways across cobblestones to either disappear again to its home below the city or form "mystery puddles", puddles that form in the streets on hot days that are often of dubious origin. Water also flows beneath the city in the dark layers of history. Some of the most ancient buildings have in their deepest depths glimpses of the underground rivers that flow below.

Flow of Pedestrians: The streets of Rome form an intricate network of pedestrian flow. This current behaves similarly to any water or electrical network. In the open piazzas, people move slowly, often they are even stationary, these are the lakes and ponds of Rome. Here gentle waves of tourists lap the shops that line the edges. As one travels into the streets though, the experience changes, pedestrians pick up their speed, only stopping in the eddies created by benches. In the small dark streets the rush of walkers curling back and forth, bouncing from wall to wall is definite, rarely are any walkers static.

Note: It should be noted that resisting the urge to quickly move through the narrower streets can be beneficial to the curious mind.