In the hills above Arberth is a large rock in the shape of a chair. This is known as "the throne of Arberth" and local legend has it that if a person of noble birth sits on the throne, they will either see a wonder or suffer a terrible fate. One day, Pryll, Prince of Dyfed, sits on the throne. As if by magic, a woman appears, wearing a cloak of gold and riding a grey-white horse. She appears once a day for three days. None of even the fastest horses in the kingdom can catch her. On the third day, Pryll gives chase on his own horse. He too cannot catch her, but he calls out to her. Hearing his voice, she stops and reveals herself to be Rhiannon, Queen of the Otherworld, come to declare her love for him.