Yamanba (山姥) is a frequently-performed Noh play of the fifth category attributed to Zeami Motokiyo.
A female dancer, called "Hyakuma Yamanba" because of her frequent performances of songs about the character, embarks on a pilgrimage to Zenkōji in Shinano Province, accompanied by her attendants.
The dancer decides that, as she is a pilgrim, it is fitting that she descend from her litter and proceed on foot, taking that very path.
They have not gone far when the sun sets unexpectedly, and they are offered lodgings by a mysterious old woman, who, after they accept, demands that the dancer perform the Yamanba song.
On his departure, the dancer dares not refuse Yama-uba's request — but it is the crone herself who performs the long dance which ends the play.