Canossa (Reggiano: Canòsa) is a comune and castle town in the Province of Reggio Emilia, Emilia-Romagna, northern Italy.

It is where Holy Roman Emperor Henry IV did penance in 1077 and stood three days bare-headed in the snow to reverse his excommunication by Pope Gregory VII.

Matilda invited Pope Gregory VII to take refuge in Canossa Castle in 1076/77 during the dispute with Henry IV, the Holy Roman Emperor.

In the end their joint fears proved groundless when Henry appeared in the guise of a penitent and begged for forgiveness and reinstatement in the church.

The nearby Tempietto del Petrarca, Canossa celebrates the refuge of Petrarch offered here by a local warlord.