Around the year 1000, on the foundations of a pre-existing Roman tower, was built a fortified garrison, part of the defense system of the coast, first nucleus of the future papal Castle. In 1254 the estate was in the will of Albert Norman, with the name of villa San Giorgio, probably in honor of the Saint to whom this family native to North was particularly devoted.
Later the property passed to Alberteschi and then to the Anguillara. The latter worked great works of reclamation of the area, celebrated through the dissemination of the legend of St. George and the Dragon (Malagrotta Legend), precisely because they descended from Normans (presence of the Dragon in the arms of Anguillara).
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.

