The patron of Donnas is Saint Peter in Chains, celebrated on 1 August in the parish church that bears his name.
Every winter the old village hosts the Foire de Saint-Ours de Donnas, held a week before the one in Aosta. At the start of October, instead, comes the Foire du raisin et des châtaignes, the grape and chestnut festival devoted to the products that symbolise Donnas and the lower Aosta Valley: here is grown the chestnut variety called donnasc, which some believe gave the town its very name.
