From The Heretic Knowledge Vault
Rosteriel is a smallish town somewhere in the northern part of the Northern Confederacy, not too far from the frighteningly misogynistic Confederacy city Goriel, scene of the longest-running thread group in Errant Road. It is significant as the home of important NPC Marge Vatnikov, dowager head (to the extent that a woman can be the head of anything in Gorielian territory) of the dominant clan in town, friend and confidante of PC Therese, and source of Big Reveal-type information regarding the shadowy Convergence that -- spoiler alert -- is the collective Big Bad of the game. It is also important as the site of a node on an ancient, probably dwarven transportation system, used by PC Lillith and her NPC husband Brad to escape from Goriel and start a new life in Lillith's home village of Santuariel.
We don't know much about Rosteriel itself, except that Lady Vatnikov's influence is showing some signs of moving it away from the misogyny of its larger, boorish neighbor city. That's probably a good thing.