The Cave of the Golden Rose is cave deep in the woods that can be reached from by The King and Romualdo's castles. The Cave is feared by many because it contains a Beast that eats only women, which the Beast claims is because they taste better. In Romualdo's kingdom, at least, it's understood that the Beast is the thing most feared by women.

When Fantaghirò was born, her father The King initially considered her cursed, and brought her to the Cave in order to sacrifice her to the Beast. He was stopped by the White Witch before he could kill her. He considered this a sign from the gods that he was about to make a serious mistake, asked for forgiveness, and decided that no one would speak of the Cave in their kingdom ever again. Fantaghirò grows up not knowing about the Cave or the Beast within it.

Years later Romualdo decided to bring Fantaghirò (disguised as Count Gooseten) to the Cave in order to confirm whether she was a man or a woman. The plan was foolhardy, as Fantaghirò would have had to die in order to confirm her gender. If she were male, Romualdo would find a body, if she were female, he wouldn't because she would have been eaten.

Luckily, Fantaghirò survives the encounter with the Beast. She enters the Cave bravely, excited to learn about the mysterious Beast, and accidentally falls into what at first appears to be a cavern, with the "golden rose" hanging from the ceiling. After talking to the Beast she realizes that she is inside its mouth, and the "golden rose" is actually its uvula. Fantaghirò manages to get out by using one of the Goose's feathers to tickle the uvula, causing the Beast to sneeze and allowing her to escape. She leaves the Cave unharmed, leaving Romualdo and his friends befuddled and impressed.