In addition to the small cars, you'll notice a lot of buses in the pictures of this gallery. Public transportation is big in Rome and easy to use from what I've read. We didn't go on any public buses or the subway because we had a tightly controlled agenda and to be honest, the cabs in the city are everywhere and all you really need as a tourist. Btw, notice the lack of lane markers in the direction we were facing when I took this picture?