Thalos once had been a large city, well known for its trade with both Humans  and Dwarves.
But then an onslaught of an evil mage, supported by lamia and an beholder, reduced the town to ruins. Now it is inhabited by foul creatures, lurking there and waiting for anyone foolish enough to enter their territory or wandering the Dwarven Forest unarmed.
Dwarven scouts reported, that there are rich treasures hidden in this town. However, an experienced party would be needed to conquer Thalos.