In the development of Fellport, the breakwater that encircles the harbor came first, and the two spires flanking the entryway came soon after. Originally a pair of bonfires flanked the harbor's mouth, but bigger ships had a harder time seeing them, so the Ionian Empire commissioned a pair of sturdy towers, slender but strong. The tops of both towers maintained blazing fires all day and night, and ships almost never hit the breakwater again.
As Fellport grew, so did piracy. The spires expanded from simple signal towers to the last shrine on the way out of town on the right (the Spire of Light), and the dungeon and execution area on the left (the Pirate's Spire). The tower itself added several strong cells all around the outside, each cramped room with its own tiny window to let in the elements but prevent escape. In the bad times, cages hung around the outside of the spire, holding prisoners in fully-exposed cells. The wharf nearest the Pirate's Spire soon sprouted gibbets that dispatched many pirates, or held the bodies after even more gruesome deaths. It became known as Execution Wharf.
Many pirates held in the Pirate's Spire died of starvation, exposure to the elements, hanging, stabbing, poison, and the occasional defenestration from the top of the tower. If the victim survived the first fall, they got dragged up the circular stairs for another 60-foot fall onto the stones of the breakwater. Historians now classify much of the "justice" dispensed as heinous war crimes.
Pirate's Spire doesn't hold prisoners much any more, and the city has largely abandoned it except to maintain the magical red signal fire that burns without heat or smoke all the time. A group of historians named Justice Remembered currently negotiate with the Fellport Council to take over the tower and turn it into a museum showcasing crime and punishment through the ages. The city enjoys some rental income during every Gostra Festival, as the Pirate's Spire looks down over the pole right next door, and Justice Remembered plans on continuing the practice, using those proceeds to keep the museum solvent.