Howard Shore did such a great job at composing and orchestrating the music for the LOTR and the Hobbit.
One of my favorite themes is the Rohan theme. I learned that the theme was played on an instrument called the hardanger fiddle which is a traditional Norwegian instrument. I remember Peter Jackson saying that he told Howard Shore that if the tune of a theme was hummable, then it was a good theme. I find the Rohan theme very hummable.
What are your favorite musical themes from the LOTR or the Hobbit?