Samuel Barber composed his violin concerto in 1939. The nature of its origin led to the aspect that is the weirdest: the seeming incongruity between the character of the first two movements and that of the finale. The first and second movements are lyrical and melodic, the first lasting about ten minutes, and the second movement lasts around nine minutes.
But to these two gorgeous movements Barber added a finale that is played at breakneck speed, never pausing for breath, utilizing rhythmic complexities and accents that are brutal in their effect; and this last movement only runs about four minutes.
It is incredibly virtuosic, with the solo violin playing in a perpetual, continual motion with only two orchestral breaks.
Here is violinist Gil Shaham to play it for you: