THE BROWN STONE SPIRE is Night Vale's newest spire, built in the night by unknown agents, or aliens, or animals, or just our collective imagination. THE BROWN STONE SPIRE is a malevolent entity beyond primitive human concepts such as morality, and it tempts the most desperate citizens of Night Vale, offering solutions to their problems in exchange for terrible, unspeakable costs. THE BROWN STONE SPIRE has a slogan, but it cannot be pronounced. THE BROWN STONE SPIRE is brought to you by Wendy's.
Sometimes it grants people gifts in exchange for their offerings. It may for example give a person a copy of "Harry Potter and the Chamber of Secrets" (the greater the person's offering, the better the condition of the book). 
Night Vale Community Radio host Cecil Palmer has fond memories of standing silent and trance-like with John Peters - you know, the farmer? - in front of the Ancient Chalk Spire, which was said to be the "predecessor" to THE current BROWN STONE SPIRE. It is not known if there were other, intermediary spires between the fall of the Ancient Chalk Spire and rise of THE BROWN STONE SPIRE, nor is it known whether or not there were spires before the Ancient Chalk Spire, and nor is it known exactly what is meant by the word "predecessor". Did the Ancient Chalk Spire choose to evolve into THE BROWN STONE SPIRE, or are the two spires separate entities who were eternally at war until THE BROWN STONE SPIRE triumphed over and consumed the essence of the inferior Ancient Chalk Spire? Only THE BROWN STONE SPIRE knows the answer, and we dare not ask it.
After THE BROWN STONE SPIRE materialized, the residents of Night Vale have been expected to supplicate themselves before THE BROWN STONE SPIRE after their traditional Thanksgiving feasts, crawling through the rocky desert on their hands and knees to thank THE BROWN STONE SPIRE for all it has done and, more importantly, not done. Those whose groveling pleases THE BROWN STONE SPIRE are allowed to return to their homes with their families. Those who do not please THE BROWN STONE SPIRE are met with an unspeakable fate.