Chronicles of Khaldun: Down the Glen Tramp Little Men
Vonseloth, the Shining City, sits at the mouth Sylernavian Pass. Supposedly, it was founded by eladrin and their kin from nearby Sylernavia — although no such city is recorded on any map. It is thought to be a fey city, and as such, appears and disappears according to an arcane schedule only comprehensible by the eldritch whims of Faerie.
Vonseloth is still a haven to fey creatures, and it forms a major trading post between the merchants of the Sorrowfell Plains and the merchants of the northern frontier, such as traders from Grimwald.