Built by the Major Commandery of Castile, it owes its name to the fact that it housed a third of the collected taxes, which remained in the hands of the Commander for his personal use.
Its characteristics suggest that the construction dates back to the 16th century, as seems to be confirmed by the imperial coat of arms of the Habsburgs seen on its façade.
It was the residence of, among other illustrious figures, Don Luis de Requesens y Zúñiga, Major Commander of Castile.
Currently, the old cellars house the Ethnographic Museum, and the granary serves as a magnificent exhibition hall.
