Huken City was the closest settlement to the Four Sectors' Border Region. It had been established and built from scratch by a group of merchants that thought that profit could be made from the place.
The Four Sector's Border Region was the most chaotic place in Zamuria Continent. It was incredibly vast and had unusual terrain. Moreover, thanks to the Restriction Law in the region, flying was impossible beyond a certain height. On top of that, thanks to the Predominated Vine, traveling wasn't easy through the region.
Then again, due to the massive area it covered, the Four Sectors' Border Region basically became a main region of travel if one wished to go from one sector to another in the Zamuria Continent.