The Bob Graham Round is perhaps the most gruelling of all Fell Running challenges.
Athletes have to climb 42 peaks, run about 70 miles and ascend 27 000 feet - which is about the height of Everest from sea level - all in a period of 24 hours.
The run takes place in the glorious beauty of The Lake District, with its rapidly changing weather and underfoot conditions.
It's a challenge which unites two diverse motivators of great art : human endeavour and the beauty of nature.
This year, while determined runners made their attempts at the Bob Graham Round, a young Italian composer has been writing a brand new piece of music that celebrates fell running in The Lakes.
Maurizio Malagnini had never visited Cumbria before and had never heard of fell running.
Ironically these were two of the reasons he was asked to write a new piece of work for the BBC Philharmonic Orchestra, they wanted to see how fresh eyes would be inspired.
The programme follows two stories: the development of Maurizio's composition and the attempt of two runners seeking to complete The Bob Graham Round.
How the most gruelling fell race is inspiring a composer to write a new piece of music.