Daruthrost, or the Loss Bridge , is a towering cyclopean bridge that might have once spanned the Deeprun Crevasse in eastern Iobaria in ages past. The dark stone of the central span collapsed centuries ago, leaving a quarter-mile wide gap at what would have once been the apex of the bridge. Attempts to cross the gap through flight or magic fail due to the supernaturally strong winds that howl around, as attested to by the piles of sun-bleached bones that line the banks of the Myrfrus River beneath the arch.
Built during the height of the Koloran Empire, the arch of Daruthrost was shattered before the first Iobarians began to settle the region. The first humans to come to the Deeprun Crevasse discovered the ruins of Daruthrost and settled in the ruin's stablest structures. Within a generation, Daruthrost became the primary trade hub of the Dvezda Marches, with several industries including a lumber mill, a tannery, several granaries and a dozen shops. However, when one of Iobara's many plagues swept through the Dvezda Marches, Daruthrost's sizeable population and the number of travellers and merchants who visited the town for trade turned the city into a breeding ground for disease.
Thanks to these outbreaks, trade was cut off to Daruthrost and its people were ostracized, while citizens fled by the hundreds, leading to riots and rebellions. The best-known rebellion was started by the sorcerer Kosiavitch Criath, who led his followers to slaughter plague victims to prevent its spread. The victims barricaded themselves within the upper levels of Daruthrost, where Criath's followers built living chambers within the bridge itself. The followers of Criath survived in isolation for a decade before they too were struck by the plague, resulting in panic and rioting. Those with any form of illness were thrown to their deaths over the edge of the broken bridge, but that failed to halt the plague, and in the end, there were no survivors.
The ghosts of the victims of the plagues and riots continue to haunt Daruthrost, which is known as a plague city, and the saying "All plagues start in Daruthrost" has become common throughout Iobaria.