During the ' 500 the Mattei in addition to acquiring the "diruta villa San Giorgio", came into possession of other neighboring properties that accorporarono in 1603. One of these features, called "Vaccarese" or "Vaccareccia" from pasture to Maremma cows and buffaloes that they practiced, gave its name to the entire possession.
In 1756 Camillo Rospigliosi began further renovation work giving the castle its present appearance. Turning around the walls to reach the entrance gate to the garden in front of the façade; This input is recent and replaces the previous two entrances, still visible; the first on the garden side overlooking the Arrone, where was a bridge; the main, of which little remains – is hidden among the trees on the left.
The façade of the castle is encased between two towers, crowned by a tower with large clock and enlivened by a central balcony with window, framed by a simple decoration with the diamond pattern of coat of arms Rospigliosi.
From the portal below you enter the lobby of the Chateau, on whose walls are the coats of arms in stone of the Rospigliosi and an inscription of Benedict XIV celebrant the episode captured by the Turks in Maccarese.
In 1683 Vaccarese or Maccarese was bought by Shan for 270.000 shields and the conjunction of Pallavicini with Rospigliosi transformed the castle into a country residence.