The staircase at La Meridiana is surrounded by a large sundial.  At dawn a shaft of light shines through the hole in the east wall onto the west and north walls.  In the middle of the day a spot of sunlight is reflected off a small mirror on the south wall onto the ceiling system and in the afternoon a shaft of sunlight is projected from the hole in the west wall onto the north and east walls. The dials tell time, date and zodiac (red), altitude of the sun(blue), azimuth (green) and the times of sunrise and sunset.  Click on images to enlarge them.