The Arsanias River (pronounced arr-SAH-nee-ahs) is a river that begins in the foothills of the Zakros Range before flowing southeast into the Potasomin River, and from there eventually into Lake Ciuto. Much of the river lies within the territory claimed by New Sotosa, though it is at the nation's very eastern margins.
Most gnolls of New Sotosa live around the Arsanias River. Their small settlements dot the riverbank, obscured by embankments that look natural at a first glance but which were actually built for the express purpose of hiding the gnolls' presence. For its part, the legion maintains two strongholds along the Arsanias, at Fort Hovalia in the north and West Watch in the south, though aside from occasional patrols the legionaries generally avoid the rest of the river.