[Almaron]

Argh, I'm a fool. Three Rivers Hold does exist, it's just...mentioned oddly. It's the hold in Dragon's Fire that Halla gets caught at when the two Shunned women try to steal from a riverboat captain, but it's not named until Halla meets Lord Fenner. According to the scene, it's located at the "Highest part of the River Crom" - I assume this means the left tributary of the Great Dunto River, since they started there, and not the Crom River which is mentioned at another point.

For goodness sakes...who makes two different locations with almost exactly the same name...and in the same book?