Rome has a hundred, at least, piazzas dotting the landscape and most of them have a fountain of some sort. The roots to the fountains come from early Roman history, when aqueducts were first built to bring water to the city. It became a custom to create a fountain, or mostra,at the entry point of an aqueduct in the city. Back then there were 39 fountains and 500 plus basins where people could get clean drinking water. Just building the aqueducts was a feat in itself. Plus, they had two aqueducts as a source for each major fountain so that if one was being worked on, there would still be water available. What planning!
The most famous fountain is Trevi Fountain. The fountain is a spectacular combination of heroes and gods, horses and flowing water. The effect is breathtaking, and extremely popular with the tourists. The place was absolutely mobbed both times we went. It's because of the lighting...one time it was sunset and the next in the middle of the day. Jeff, however, is the custodian of the spectacular pictures.
Piazza de Navona has a number of striking fountains, apparently one isn't enough when you have to compete with the popularity of some other fountains. This one includes Neptune fighting an octopus! Just for added interest, there are also some added horses and other figures along the outside of the basin. Hmmm....my picture seems to have disappeared into cyberspace. Check out the link for pictures of it.