Location from A Song of Ice and Fire by George R.R. Martin
The Tully stronghold at the confluence of the Tumblestone and Red Fork — a castle that can flood its own moat to become an island fortress, sitting at the crossroads of every war in Westeros.
Riverrun is a fortress built for a family that has always been caught between larger powers, and its design reflects that pragmatism — it can be isolated by water in hours, making it nearly impossible to storm but also nearly impossible to relieve. The Riverlands have no natural borders, which means every war in Westeros flows through Tully territory like the rivers that define it. The castle's halls are comfortable rather than grand, and the Tullys who occupy them are known for loyalty, stubbornness, and a tendency to get pulled into conflicts not of their making. Catelyn Stark grew up watching the rivers from these walls, and Edmure Tully defended them with more courage than strategic sense. The castle has changed hands more than any other great seat, because holding the Riverlands means holding the center of the map.
A triangular castle of red sandstone sits where two rivers meet, its water gate opening onto the current. Sluice gates can flood the surrounding land to turn Riverrun into an island. The Tully trout banners fly from modest but sturdy towers that reflect wavering river light across their walls.
Also known as: Riverrun, the Tully seat