First broadcast : August 9th at 8:40pm Paris time / 6:40pm GMT *
The Somme, the scene in 1916 of the bloodiest and most senseless battle of World War I.
More than a million died, including a whole generation of young soldiers from Great Britain, Canada and Australia.
Today the front-line is marked by the countless military graves of former British Empire soldiers.
Our reporters met the descendants of soldiers and visitors from all over the world who have gathered to honour the memory of the fallen.