The course of the River Mern
The River Mern, often simply called the Mern, is a river in the Imperial Domain, running from the Mernel Mountains to Lake Arcanos. The waters of the Mern are a striking sapphire blue; as well as fast, violent, and frigid, but also deep, allowing for their use as a major artery of trade between Mernel and the Imperial Domain.
Along the Mern are the Mernforts, a series of forts built by the Kings in the Old Castle to defend their lands and trading boats from Mernelian and Y'kanosi raiders.