Early residents of Pijal constructed Celestial Watchtowers as fortified locations to keep a close eye on their soulcraft. As space travel became safer, these Watchtowers became obsolete and decayed. The blackguards, who were treacherous members of the Pijal royal guard, refurbished one of these structures into a military base. These inhabitants lived in Pijal and practiced soulcraft. The towers were built to watch over their soulcraft. Space travel becoming safer led to the abandonment of the towers. The blackguards committed treason when they renovated the tower. They were part of the Pijal royal guard.
Claudia Gray's 2019 novel, Master & Apprentice, featured the Celestial Watchtowers. The towers were written about by Claudia Gray.