I am also voting for the Trevi fountain. If there are crowds there, they will cheer you and your proposal will be unforgettable. She will love it.

p.s.

Bring a couple of coins and ask her to make a wish. I'd bet hers matches up with yours. It would be delightful if the violinist could find you at that moment.

Shabass-as I've said before, (just recently on another thread) Trevi Fountain at night, is one of the most beautiful sights in the entire world, and unless you are going in the middle of summer, if you go late at night, you'll have few people there, did you consider that? Personally, I think it's a wonderful place to propose, and more importantly, it's HER favorite place, as it is one of mine. I absolutely would pop the question there, but do it sometime after 10pm-you most certainly will not have crowds there then.

I love the idea of the musicians! How wonderfully romantic! The Trevi Fountain area is crowded, so perhaps you can do late at night (after a nice dinner close by?).

You guys are great, so much good advice. I'll put some more thought into the musicians but doing this later in the day is exactly what I want. I also like the cion idea and the idea of proposing in Italian.

You know what? I actually like the Trevi Fountain idea. Yes, it will be crowded with people from every corner of the globe. But so what?

Once you drop to one knee and whip out the hardware, you'll get an audience...and probably an ovation when she says "yes". I think that's great.

Not for everyone, I guess, but pretty damned memorable!

I agree with all the fellow travelers about how beautiful the Trevi Fountain is at night. My wife and I love just sitting at the fountain and relaxing. The crowds come and go all night long, but they do thin out later. My suggestion to you would be to sit awhile with your girlfriend and enjoy the beautiful stone work, and sounds of the water. When the crowds thin out ask her to throw a coin into the water with you. And you will know when to pop the question.
Good Luck, Louie and Vera.

The ideas about Trevi sound great. I'd say ditch the idea of musicians though.

You (she) wants your attention on her, not looking around to find the musicians, wondering if the 15min you paid for are about to run out, etc.

Hire some musicians later in a piazza if you wish to dance, but keep the propasal moment just between you 2 (and the surrounding public)

if you are going to do it in public be damned sure she is going to say yes.

don't ask me why I say this.