Rome is known for it's fountains. Nearly all of the most popular tourist sites in this ancient city have fountains. They are found in nearly every piazza and were historically used to supply drinking water to the residents of the city (and the water is still drinkable). Some, like Trevi Fountain, are more elaborate than others, but many of the fountains have been designed my masters of art and architecture: Gian Lorenzo Bernini, Giacomo della Porta, Nicola Salvi, among others. What's even more impressive is that all of the fountains are gravity fed.