Ganuenta (Colijnsplaat)
Ganuenta is only known from the votive altars dedicated to the ancient goddess Nehalennia, which were discovered in 1970-1974 on the Colijnsplaat in the Oosterschelde estuary. Probably, Ganuenta was the capital of the Frisiavones, but since the sea has swallowed up this area, hardly anything is known about this once important international port.
No votive altar can be dated after 227, and archaeologists have discovered almost nothing from late antiquity in this part of the Netherlands. This suggests that the site and the area were abandoned at some moment in the mid-third century. It is likely that the sea had become more active in what is called the Duinkerke-2-transgression phase.
In itself, this would not have been disastrous, but the inhabitants of the coastal region of Germania Inferior had been extracting salty peat from the mud flats (it was used to produce salt). The natural defense against the water had disappeared, and the sea could easily destroy the coast.