"The Sesh", centered around the River Sesh.

The River Sesh is a large river in the center of the known world. Its valley, also called the Sesh, is one of the so-called "cradles of civilization", a region where agriculture and city-building spontaneously arose. Originally home to the Bahran, Seshweay, and Arkage civilizations, it became one of the most fought over rivers in history, to the point where many said (only half in jest) that the river was more blood than water. The river originates from three tributaries, and is home to many waterfalls and cataracts. Near the joining of the tributaries lies the great city of Magha, the heart of Satar culture. Despite its short length, the river terminates in a large delta where one can find the city of Seis, another one of history's greatest cities. After being viciously balkanized religiously and ethnically by invasions from the Satar, Accans, and Uggor, the native Seshite peoples have mingled with their invaders so much and so long as to be nearly indistinguishable.