The Drowning Wave

Long ago, before the Sunken Fields sank, they were fertile farms and lush grazing for cattle, providing the region with grain and fresh vegetables. This made Rille one of the wealthiest farming settlements in the area, especially in combination with the fish from Lake Trika.
It was not to last.
It is said that Kynath, the great sea serpent was engaged in a great battle, far out to sea. With his great tail, struck his opponent with such force that it created an unfathomably tall wave that headed straight towards the shores of Vanelle. The wave came from the south, breaking against islands and cliffs as it moved past, causing terrible destruction. The Isle of Irricam was hit hard; the wave submerged most of the island for many days in its wake. Great swathes of rock were crushed into the ocean all along the mainland shore, changing its outline forever.
Hardest hit of all were the fields in the valley between Rille and the The Verdant Ocean. The shallow valley had no hills or cliffs to protect it from the might of the ocean as it roared in, submerging the entire region in slat water, killing crops, cattle and people indiscriminately as it flooded everything. It carved out the soil, uprooted trees and destroyed whole farms. And then it stayed, slowly seeping into the earth, saturating the ground and creating vast pools of salty mud.
Rille was hit hard. The flood damage was vast, as was the cost of human life. The town's productive farms were no more and the land was no longer suitable for cattle. Many people left, and those who stayed made their living fishing or hunting. Most people scraped by; many didn't.
Over the years, the valley turned into the swamp we know as the Sunken Fields today. Plants and wildlife moved in, but the water stayed, making the ground impossible to farm, eventually creating the hostile environment we now know.

Type

Natural