Each pillar takes control of the map in a circular area around it with a radius of 250 tiles, or 500 feet.
They appear at four locations equally spaced across the map (see pillar spawning mechanics below), and are completely stationary, apart from slowly bobbing up and down in place. The Celestial Pillars (also known as the Lunar Pillars, Lunar Towers, or Celestial Towers) are four late- Hardmode bosses that appear during the Lunar Events after the Lunatic Cultist has been defeated.