Different versions of the legend share several basic common elements. King
Gradlon (Gralon in
Breton) ruled in Ys, a city built on land reclaimed from the sea, sometimes described as rich in commerce and the arts, with Gradlon's palace being made of marble, cedar and gold. In some versions, Gradlon built the city upon the request of his daughter
Dahut, who loved the sea. To protect Ys from inundation, a
dike was built with a gate that was opened for ships during low tide. The one key that opened the gate was held by the king. Most versions of the legend present Gradlon as a pious man, and his daughter, Princess Dahut, as wayward.
Dahut (sometimes called Ahez) is often presented as frivolous and an unrepentant sinner, or, sometimes, as a
sorceress. However, in another version, that of an ancient ballad, Gradlon himself is blamed by his people for extravagances of every kind. In most variations, Dahut acquires the key to the dikes from Gradlon, and its misuse leads to catastrophe. Commonly, Dahut steals the keys (made either of silver or gold) from her father while he sleeps, either to allow her lover inside for a banquet or after being persuaded to do so by her flattering lover. She opens the gates of the dikes, either in a wine-induced folly or by mistake, believing she is opening the city gates. The sea inundates the city, killing everyone but the king. A Saint (either
St. Gwénnolé or
St. Corentin) wakes the sleeping king and urges him to flee. The king mounts his horse and takes his daughter with him. As the water is about to overtake him, a voice calls out: "
Throw the demon thou carriest into the sea, if thou dost not desire to perish." Dahut falls from the horse's back, and Gradlon is saved. In Le Braz's version, it is Gradlon himself who throws her off on St. Gwénnolé's orders. In some versions, after falling into the sea, Dahut becomes a
morgen or mermaid who continues haunting the sea, and can be seen combing her golden hair and singing sad songs. Some 19th-century folklorists also collected old beliefs that said during low tides the ruins of Ys could be seen, or the sound of its
carillon could be heard. In Le Grand's version, St. Gwénnolé goes to see Gradlon and warns him about the sins being committed in the city, which is absorbed in luxury, debauchery and vanity. God has warned St. Gwénnolé that he is going to punish the city, and the Saint tells the king to flee since God's wrath is about to fall upon the city. The king flees the city on horseback. A storm falls upon the city and quickly inundates it. The main culprit is Princess Dahut, the king's indecent daughter, who has stolen the key, symbol of royalty, from around her father's neck. Gradlon takes refuge in
Quimper. Other versions of the legend tell that Ys was founded more than 2,000 years before Gradlon's reign in a then-dry location off the current coast of the Bay of Douarnenez, but the Breton coast had slowly given way to the sea so that Ys was under it at each high tide when Gradlon's reign began. , abbé de Landévennec, sauvant le roi Gradlon lors de la submersion de la ville d'Ys" Church of Saint-Germain Kerlaz. ==Development of the legend==