A tall thin tower :D
There are two in Lego universe. One is in crux prime near the maelstrom quarry and one is just a planet you can get to from nimbus station.
Monks in the tower of a monastery often engaged in various activities such as prayer, meditation, and study. The tower served as a place for solitude, allowing monks to focus on their spiritual practices and reflection. Additionally, it might have been used for administrative tasks or as a lookout point for the monastery's surroundings. The tower symbolized both a physical and spiritual elevation, emphasizing the monks' commitment to their faith.