Here is the whole entry:
Located south of Laselle. The marsh itself is a mix of swamp, streams, slow moving rivulets, rivers. small islands and mud humps that are an equal mix of earth and water. Interspersed with all of that are islands of grass and brush and dense stands of trees. Any movement through that is impossible. A person would sink up to their hips in mud that seemed to be everywhere. Long known as a refuge. When the Suielman invaded the Northern Midlands Centli survivors fled into the marsh. Centuries later when the Lutins invaded surviving Suielman also fled to the marsh. A community of people still live there. It is effectively impassable to armies. The one Suielman road that runs north from Kormley detours around the marsh. Legends speak of a Lutin tribe that took refuge there but it's never been proven or disproved.
The marsh sits at one end of a short branch of the Metamor river. In the past the main branch of the Metamor river ran past this way. But at some point the river changed course and now follows it's current path to the sea. Why the change happened remains unknown. When it happened also remains unknown. Some legends speak of a cataclysm (exactly what changes from tale to tale). Other legends say it was deliberately diverted by (insert some group long dead here - Tened, Sueliman) for reasons unknown. Others think it changed course as part of some natural process. Rivers do change course.