The "Lady of Llyn y Fan Fach" is a figure from Welsh folklore, associated with a lake in the Brecon Beacons National Park. According to legend, she is a beautiful woman who emerged from the waters of Llyn y Fan Fach, captivating a local farmer. Their union led to the birth of three sons, but she had a condition that he must never strike her. When the farmer accidentally broke this promise, the lady returned to the lake, taking her children with her. The story symbolizes themes of love, loss, and the connection between humans and nature, making it a significant part of Welsh mythology.