They say that the broken ruins in Arelith forest were once the beautiful city of Benwick, which at it’s center had a mighty fortress known as Light Keep. And below it a portal to the very hells itself, guarded by a group of Paladins and another fortress, known as The Last Bastion.
This glorious city stood for many years as a bastion of goodness within Arelith, until it fell to Devils, when a group of infernalists took advantage of a weakening of the planes, known as the Rift Crisis, to summon a mighty army which besieged Benwick.
At the same time as this happened, an army rose up from the Hells and attacked the Last Bastion. With the help of a large group of adventurers, the attack was rebuffed, but the Last Bastion fell, and the portal to the Hells was unguarded, protected only by a magical barrier.
The Keep held on for a few more years, but only just. Constantly attacked and threatened by it’s foes. Eventually the Captain of the Keep, Thomas Miller, ended up vassaling the Keep to the infernalists. Some say he was bad from the start, others that he broke under pressure.
Either way, shortly after that the seal to the hells was smashed open, devils invaded, and Benwick fell. You can still meet some of the refugees here and about, bemoaning their beautiful lost city.