Seeing as I spent the past five days writing a paper about Felix Mendelssohn, it's only appropriate that I write about him here.
Mendelssohn was a composer who, during the "progressive" Romantic era, chose to fall back on the Classical idiom. Thus he wrote music that, to a 19th-century audience, seemed dated. Of course, he was far too young to be old-fashioned. He simply wrote what he loved- music in the vein of Bach or Beethoven, but he wrote it from a 19th-century perspective. This quality makes his music uniquely beautiful.
So, check out Mendelssohn's 3rd Symphony, also known as "Scottish" (A Minor). It's really wonderful and moving.