There have always been stories about a flood coming down to wash the wicked world away.
In mythology, this tends to happen when the gods nope out of a situation. Excess and the very debatable concept of sin are the usual grounds for this sort of divine spring-cleaning. If legendary lands are on a spectrum, the utopian islands would probably be at one end and the drowned lands would be at the other. These are the cautionary tales. There are very few survivors.
Let’s start in Ker-Ys. According to Breton legend, this was a wealthy city-state on the coast of south-west Brittany, under what is now the Bay of of Douarnenez. It was protected from both its enemies and the rapacious sea by an enormous dike. Ker-Ys was ruled by Gradlon Meur, a pious Christian prince, but he lived in a beautiful marble palace decorated with cedar and gold and the city itself was a place of art and beauty and excess – no doubt the influence of Gradlon’s only child, a princess who was known for anything but piety.
Her name varies between versions of the legend – Ahès, Ahè, Dahud, Dahut – and her personality varies even more. Depending on the telling, she was either
a) a careless girl who threw a private party for her lover and drowned the city in a drunken prank gone wrong, or
b) a full-on serial killer who seduced boys then had her servants strangle them and chuck their bodies into a gorge, ultimately bewitching a young man into opening the dike for her. Ahès is described as having made ‘a crown of her vices and…taken as pages the seven deadly sins’, which frankly sounds a lot more awesome than I imagine it was intended to.
Whatever her motivation, the destruction of Ker-Ys is laid squarely at the princess’s door. The king was warned in time to escape and took his daughter with him, but the waters caught up with their horse and the king was told to throw off the ‘she-devil’. Ahès fell into the sea. The king survived, but the city was lost.
Ahès survived too, becoming a spirit of the sea and luring sailors to the deaths. So really, apart from an amphibious lifestyle, not that much changed for her.
The story of Lyonesse is quite similar. According to Sir Thomas Malory’s Le Morte d’Arthur, it was neighbour to Cornwall and the birthplace of the knight Tristan. The poet Lord Alfred Tennyson made Lyonesse the setting for King Arthur’s final battle, describing it evocatively in The Idylls of the King:
Then rose the King and moved his host by night
And ever pushed Sir Mordred, league by league,
Back to the sunset bound of Lyonesse—
A land of old upheaven from the abyss
By fire, to sink into the abyss again;
Where fragments of forgotten peoples dwelt,
And the long mountains ended in a coast
Of ever-shifting sand, and far away
The phantom circle of a moaning sea.
The landscape of Lyonesse received another loving description in Alan Seeger’s 1917 poem ‘Lyonesse’, quoted below:
In Lyonesse was beauty enough, men say:
Long Summer loaded the orchards to excess,
And fertile lowlands lengthening far away,
Came a term to that land’s old favoredness:
Past the sea-walls, crumbled in thundering spray,
Rolled the green waves, ravening, merciless.
Through bearded boughs immobile in cool decay,
Where sea-bloom covers corroding palaces,
The mermaid glides with a curious glance to-day,
How exactly Lyonesse came to sink beneath the sea is something of a mystery. None of the sources I have to hand go into any detail at all. This sort of thing just happens sometimes.
It happened, for instance, in Wales. Cantre’r Gwaelod, also known as Maes Gwyddno, is a lost land in Welsh legend, underneath what is now Cardigan Bay. This was part of the kingdom of Meirionnydd, with Caer Wyddno was its capital. In one early version of the legend, the land was drowned when a maiden named Mererid allowed her well to overflow; in another version, two princes were charged with the management of the sluice gates that protected their land. One was called Seithenyn and due to his drunken negligence, the gate was left open, allowing the sea to pour through. Folklore has it that the church bells still ring in times of trouble.
It has been suggested that this story shares origins with another drowned land in Wales, known as Llys Helig. Rumoured to be under what is now Conwy Bay, it was ruled by Helig ap Glannawg. Once again, the blame for the downfall of the kingdom is laid at the feet of a wicked princess: Helig’s daughter Gwendud. A beautiful girl with freezing arrogance, she told her suitor Tathal that she would not marry him unless he wore a nobleman’s golden torque. Tathal then went out and promptly killed a nobleman for his torque, and told Gwendud that he had won it in a duel with an outlaw. Which, I’d like to point out was a hundred percent his own decision, and a terrible decision it was too, because the nobleman’s ghost rocked up and cursed the entire family. Four generations later, the curse finally came to fruition as the sea came welling up under the castle and swallowed Llys Helig whole.
The moral of the story seems to be, if disaster is lapping at your heels, find a woman to blame for it. And if that is blame you’re willing to take, go forth and make your crown of vices.
These stories vary wildly depending on time and teller. If you know an alternative version, I would love to hear it!
References: The Enchanted World: Fabled Lands by Time-Life Books (Time-Life Books, 1986), http://www.oxfordreference.com/view/10.1093/oi/authority.20110803125227732, http://www.ancient-origins.net/news-myths-legends-europe/lost-land-lyonesse-legendary-city-bottom-sea-002490, http://d.lib.rochester.edu/camelot/text/seeger-lyonesse, https://www.historic-uk.com/HistoryUK/HistoryofWales/Tyno-Helig-The-Welsh-Atlantis/, https://en.wikipedia.org/wiki/Llys_Helig, http://www.bbc.co.uk/legacies/myths_legends/wales/w_mid/article_3.shtml, The Illustrated Encyclopaedia of Fairies – Anna Franklin (Vega, 2002), Tennyson: Poems and Plays by Lord Alfred Tennyson, ed. T. Herbert Warren (Oxford Paperbacks, 1975)