Osterbija is known as "The Land with One Entrance."
This name is a lie, as it turns out, for there is another path into the fortress-country, a path even less plausible to take by force than the Tiger's Gate of Tenja.
That path is Sukataka Rhomba. the Osterbs call it Crna Katakomba, or "The Black Catacombs." In Southern Osterbija and northern Kalmacia, this Dwarf Hold straddles the impenetrable mountain range, trading with both sides in a limited fashion (part of their agreement of peace with both parties) and supplying both with fine steel weapons.
Rhomba has never suffered a war with either of its human neighbors, and has lived in relative peace with all of them throughout the ages. However, it has suffered its own share of problems. Some sort of curse is said to sit on the great mountain under which the great city was hewn from the stone and earth. The curse of the undead lands easily on any corpse laid to rest beneath those mountains – and yet the dwarves of Crna Katakomba, ever proud and loyal to their ancestors, refuse to burn or destroy the bodies of their dead, instead burying them in stone pits filled with cement, laying them to rest in great tombs that know no sound. But the bodies do not cease to be, and the undead are patient creatures indeed. They are still around, and from time to time, when the world-serpent shakes its tail, and stone cracks and cement breaks, the undead emerge from the depths of Rhomba, rushing to free their bretheren, as though imbued with some dark intellect by their eons of captivity.
These catastrophies have spilled out into Osterbija and Kalmacia before, thousands of undead dwarves pouring out of the hills into the lowlands, some horribly and grotesquely altered by dark forces to aid in their digging free of their confines – and for slaughtering the living. The Dwarves or Rhomba themselves have grown quite adept at fighting the undead, since corpses will often rise before they can be buried.