The Vaults are an area consisting of deep, ice-cut valleys, frozen glaciers and towering heights that form the junction between the Black Mountains and the Grey Mountains.[1a]
Being the high mountains where the Black, Grey, and Apuccini Mountain ranges all meet, the Vaults are the focus of the fragmented Border Princes. Each time the incursions of Chaos have overrun the area, the surviving Princes and their armies have gathered in the shadows of the mountain to draw strength and launch their counter-attack. Each time they have succeeded, despite the complete lack of assistance from their neighbours. The Vaults' verdant hanging valleys provide excellent pasture for cattle and nutritious, if modest, harvests. The rugged terrain is also ideal guerilla country, and all kinds of brigands and rogue adventurers have bases here.
Which is not to say that the Princes are not brigands and rogue adventurers themselves. Lying south of the Black Mountains and between the Apuccinis and the Black Gulf, the region known as the Border Princes is a sparsley populated, rather bleak area with large tracts of untamed wilderness which are frequently roamed by goblinoids from the Badlands.