Source: The Inner Sea World Guide, pg(s). 156-157
Haldun is a town on the southern edge of the nation of Rahadoum. It is situated on the main pass linking Rahadoum with the southern lands. At one time it was a thriving centre of trade, dealing with Lirgen and the other lands to the south. The advent of the Eye of Abendego destroyed Lirgen, turning the area into a hurricane-blasted wilderness.
Today Haldun is a fortress town, guarding Rahadoum against incursions of monsters and cultists. It is the centre of the defensive network known as the Rainwall. Its inhabitants are a hardy folk who take a perverse pride in their harsh lives, and see the devastation to the south as a warning as to what happens to those who trust their lives to the gods.