Venus and the Pleiades held a central place in Mesoamerica. The 584-day synodic cycle of Venus was calculated with extraordinary precision by multiple cultures of the region, and its appearance on the horizon marked critical dates in the agricultural and ritual calendar. The Pleiades, for their part, were the clock of the year: their heliacal rising at the start of the rainy season signaled the moment to prepare the land, and their disappearance marked the close of the cycle. That both phenomena appear represented in the same space at Tetitla—Venus on the wall, the possible Pleiades on the adjacent floor—suggests this room served a calendrical function, not merely a decorative one.