In my opinion, an hour before sunrise is the best time to visit Trevi Fountain. It's peaceful, beautiful, and you feel like it's all yours. During the day you can hardly see it among the hordes of tourists and trinket peddlers.
I extended some artistic license on this image, namely removing the barrier that surrounds the fountain. It's actually a combination of a shot taken on the steps in front and another wider angle from further back in the piazza. I also evened out some color casts on the facade, cleaned up some street trash, toned down a few hot spots, and added a hint of reflection in the water to spice up this meatball. And of course added the title at the bottom.