Odysséa Nantes colors the streets of Nantes pink each March for a breast-cancer fundraising run and walk. The event welcomes women, men, and children, offering a timed 10 km road race, a 5 km run or walk, and a 1 km race for kids. It begins at Cours Saint-Pierre and is grounded in local support for breast-cancer research, prevention, and patient care.
The route guides participants through Nantes and across the Loire bridges, connecting the day to the city itself rather than a secluded park. Approximately 19,500 to 19,600 people participate, with one recent edition generating 218,000 euros. Since 2007, over 211,500 individuals have completed Odysséa Nantes, raising 1,697,400 euros. Funds benefit local organizations such as the Institut de Cancérologie de l’Ouest, the Loire-Atlantique branch of the Ligue Contre le Cancer, and the CHU de Nantes endowment fund.