Located in the heart of Turin, in what was supposed to be the castrum or Quadrilatero Romano, the complex stands on what, at the time of the ancient Roman colony of Julia Augusta Taurinorum, was called Porta Praetoria (for other historians it was instead the Porta Decumana ), from which one entered the Decumano Maximo entering the eastern part.
Here, in fact, we had access to the city from the side of the Po, which was, due to its strategic position, carefully defended; after the fall of the Western Roman Empire, the door was transformed into a fortress, adapted to the city defense, given the obvious importance of this way of communication, even if it maintained its original function of passage with the opening in the ancient Roman wall.
The Civic Museum of Ancient Art is located in the building. This is a combination of two thousand years of History of Turin, from the ancient eastern door of the Roman colony of Julia Augusta Taurinorum to a defensive Casaforte, then to Castello proper, symbol of the Savoy power until at least the 16th century, when the current Palazzo Reale, as the seat of the Duke of Savoy.
The western part of the first medieval complex was then called Palazzo Madama because it was first inhabited by Madame Cristina of Bourbon-France, called the first Royal Madame, in the period 1620-1663 around, then by Maria Giovanna Battista of Savoy-Nemours, called the second Madama Reale, in the period 1666-1724. It was for the latter that the present façade was designed, in 1716-1718, by the court architect Filippo Juvarra.