Samuel Barber's Adagio for Strings has been labeled “the saddest music ever written,” gaining status in the United States as the unofficial anthem of national mourning. During times of collective tragedy — such as the assassination of John Kennedy or the attacks of September 11 — Adagio Strings will certainly make an appearance. It has also been used with tragic effect in numerous films, such as The Elephant Man and Platoon. Although the Adagio is traditionally performed by string orchestra, Barber originally composed it as the second movement of his String Quartet, Op. 11. The version embedded below is from the original version for string quartet.