hmmm. I'm not so good with sonatas and all, but I DO know that Sonata No. 14 "Moonlight" (OR Moonlight Sonata, whichever you want to call it) by Beethoven was written during the late-classical early-romantic period.

I know the piece is like, 30 mins long (the 1st, 2nd and 3rd parts all together) but the first movement is kind of dark-ish, romantic-ish? yes. ;D