The Grand Raid de la Réunion, also called La diagonale des fous (The Bishops'/Madmen's Diagonal) is a mountain ultramarathon race. The race takes place annually in October on Réunion island, a French overseas department in the Indian Ocean, situated between Madagascar and Mauritius. The 162 km route with 9643 m of elevation gain is reputed to be highly challenging, brutally difficult and one of the hardest footraces in the world. Category of course Three races are held at the same time: the Grand-Raid or Diagonale des Fous — with of altitude gain the Semi-Raid or Trail of Bourbon — with of gain Mascareignes Raid — with of gain Dates of races in 2017 25th edition of the Diagonale des fous: 19 to 22 October 18th edition of the Trail de Bourbon: October 7th edition of the Mascareignes: October Winners Men Women References Related books "Grand Raid Reunion Island", a 68 pages comic book edited by UltraBD External links Official web site of Grand Raid de la Réunion Official forum of the web site of Grand Raid de la Réunion Ultra-Trail World Tour Sports competitions in Réunion Athletics in Réunion Recurring sporting events established in 1989 1989 establishments in Réunion Ultramarathons in France Trail running competitions