The Asarwe Basin is dominated by the mighty Asarwe River that originates in the distant mountains of the Stille Wächter (Silent Guardians). Only the lands lying north of the river itself are usually counted as being part of the region. The southern reaches of the actual river basin is counted as part of the Plains States region. The reason is one of climate – most of the precipitation that feeds the river falls in the mountains to the north, and then flows by way of numerous streams and smaller rivers south through the Coulladaraight before emptying into the Asarwe. The lands south of the river see little in the way of rainfall and there are far fewer secondary rivers and streams. So while the areas adjacent to the river are fertile enough, you do not have to travel very far before the land turns arid. On the northern side the land is much more fertile, and although Sendoure can have long and very dry summers it is nothing compared to what you get in say Binsada or Irbouda. Where the Asarwe approaches the sea it swells into a vast river delta that is easily the size of an entire kingdom.
Human settlement of the region came relatively late. Rohrmarch was settled by Brechts that found the Khurinlach and established a presence along its eastern shores. Later they followed the Khurinbyrn to the sea and settled the lands along the coast. Sendoure came to be dominated by Khinasi settlers, descendants of horse nomads of the plains. They settled the river valley and grew crops there, and in time they cleared away much of the light forest that grew there and made themselves a true kingdom. Rheulgard was long left alone by humans, but when the sidhe retreated into Coullabhie, Brechts slowly migrated down from the Southern Basin region. Coullabhie remains in elven hands and is arguably the most powerful sidhe realm remaining in Cerilia. At some point halflings flocked in large numbers to the little-used area know known as the Burrows. It is the only true halfling kingdom in Cerilia. Some humans make a living in the Asarwe delta, but swamplands are also home to elder creatures – and a fearsome awnshegh called the Hydra.
