For a food question, this is a tough one for me. I have no idea what my first one was, where I might have been, or under which name it went.
(Sub, hero, hoagie, grinder, and I think po' boy is similar....)
The reason I threw "hoagie" up to vixmom is that one of the most memorable ones I ever had was a delicious Italian hoagie in Philadelphia. And I can even tell you when. It was in the year 1983, and I swear (there I go again) I haven't had one to equal it.
But I love 'em, even while it's not something I think to get very often because they can be so messy, depending on what you load them up with.