St. Lucia's flood
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St. Lucia's flood (Sint-Luciavloed) was a massive flood that affected the Netherlands on December 14, 1287 (the day after St. Lucia Day) when a dikes broke during a storm, killing approximately 50,000 to 80,000 people in the fifth largest flood in recorded history. Much land was permanently flooded in what is now the Waddenzee and IJsselmeer. It especially affected the north of the Netherlands, particularly Friesland. The Griend disappeared almost completely under the waves. The name Zuiderzee dates from this event, as the water had merely been a shallow inland lake when the first dikes were being built, but rising North Sea levels created the "Southern Sea" when floods including this flood came in.
