鲁班
At the four corners of the wall sit towers (E) with intricate roofs boasting 72 ridges, reproducing the Pavilion of Prince Teng and the Yellow Crane Pavilion as they appeared in Song dynasty paintings. These towers are the most visible parts of the palace to commoners outside the walls, and much folklore is attached to them. According to one legend, artisans could not put a corner tower back together after it was dismantled for renovations in the early Qing dynasty, and it was only rebuilt after the intervention of carpenter-immortal Lu Ban.