Lake Flevo was a lake in what is now the Netherlands, which existed in Roman times and the early Middle Ages. Some geographers believe that this lake was not really a single lake, rather a set of several lakes connected to each other. Some texts of the middle-ages refer to this lake by the name of Almere. December 14, 1287, in what was called St. Lucia's flood during a memorable storm in Friesland and Holland, the North Sea invaded the freshwater lake, breaking and destroying several dams dunes and transformed it into a bay which was then called the Zuiderzee, meaning Southern Sea.