Prix Bertrand du Breuil Prix de Diane. In 2013 the race was renamed in memory of Bertrand du Breuil (1926-2011), the last president of the Societe d'Encouragemment, forerunner of France Galop. Prix Bertrand du Breuil The Prix Bertrand du Breuil is a Group 3 flat horse race in France open to thoroughbreds aged four years or older. It is run at Chantilly over a distance of 1,600 metres (about 1 mile), and it is scheduled to take place each year in June. The earliest version of the event was established at Chantilly in 1852. Its prize money was originally provided by the Chemin de
Prix du Moulin de Longchamp when the racecourse was built in 1856. The Prix du Moulin de Longchamp was one of two major races introduced to celebrate Longchamp's centenary in 1957. Both initially took place on the first Sunday in October, the same day as the Prix de l'Arc de Triomphe. The other race, the Prix de l'Abbaye de Longchamp, is still held at that meeting. The Prix du Moulin was moved to late September in 1974, and to the first Sunday of that month in 1980. It was formerly contested on Longchamp's middle course (the "moyenne piste"), but was switched to the main course