Daneasus is actually the most populated city in the world.
Mt. Danaesus is the location of one of the most beautiful and impressive temples to Pelor in the land, known as the Holy Temple.
The city is also a key location on the world's ley lines.
Mt. D once was the home of the Order of the Light of Pelor, which maintained a training facility known to insiders as The Zoo. After the wards were breached, and all the undead contained therein released into the general populous, the Light was forced to move their headquarters to an unused fortress elsewhere in the mountains.
The rock: It is said - though it may be just urban legend - that more rock has now been removed from the mountain-city than actually remains, and that the continued structural stability is a product of the superior dwarven engineering combined with incredible geological stability. Some also say that the presence of the ley lines bends the normal laws of physics a bit (a position reinforced by recent studies of the Grand Concert Hall, which is a physically impossible building.)
Much like an inverted cruise ship, there is a subtle caste system at work in the level of one's family's holding - the deeper, the better.