High in the mountains along the eastern border of Brevoy is the city of Skywatch. This city is built around a massive observatory that predates any known settlement in the region. Despite its age, the observatory is perfectly preserved and maintained by powerful magic. Exactly who built the observatory, and why, is unknown, although the building is clearly meant to accommodate beings much larger than humans.
In the early days of Issia, the Surtovas established a small outpost adjacent to the observatory to study it. The Aldori captured and fortified this outpost during one of the long wars between Issia and Rostland. After Choral conquered the rest of Rostland, Skywatch remained the seat of independent Aldori power for a few years, before the conqueror and his dragons burned the fortress to the ground. After razing the fortress, Choral took a great deal of interest in the observatory and began a massive project to unearth and restore it. House Rogarvia continued his work, and the current city of Skywatch was built to serve this project. Despite the scale of the project, its exact goals and much of the work remain shrouded in secrecy. On the day the Rogarvias disappeared, Skywatch sealed itself off completely from the outside world, refusing to allow anyone — even supply caravans — into or out of the settlement. So far, no message sent to Skywatch has received a reply, and divination magic cannot penetrate its ancient walls.
Sources: Pathfinder Chronicles Campaign Setting