Ys

Ys (pronounced /ˈiːs/ EESS), also spelled Is or Kêr-Is in Breton (kêr is the Breton word for "city", see caer), and Ville d'Ys in French, is a mythical city that was built on the coast of Brittany and later swallowed by the ocean. Most versions of the legend place the city in the Baie de Douarnenez.

According to some versions of the legend, Ys was built below sea level by Gradlon (Gralon in Breton), King of Cornouaille (Kerne in Breton), upon the request of his daughter Dahut (also called Ahes), who loved the sea.

In others, 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.

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.

Ys was the most beautiful and impressive city in Europe, but quickly became a city of sin under the influence of Dahut. She organized orgies and had the habit of killing her lovers when morning broke. Saint Winwaloe decried the corruption of Ys and warned of God's wrath and punishment, but was ignored by Dahut and the populace.

One day, a knight dressed in red came to Ys. Dahut asked him to come with her, and one night, he agreed. A storm broke out in the middle of the night and the waves could be heard smashing against the gate and the bronze walls. Dahut said to the knight: "Let the storm rage. The gates of the city are strong, and it is King Gradlon, my father, who owns the only key, attached to his neck." The knight replied: "Your father the king sleeps. You can now easily take his key." Dahut stole the key from her father and gave it to the knight, who was none other than the devil. The devil, or, in another version of the story, a wine-besotted Dahut herself, then opened the gate.

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