Paço Real de Caxias was projected by Infant D. Francisco de Bragança and completed by the future king D. Pedro V, who used it as hollidays residence for the royal family.
Initially, it included the farm, the geometric gardens of french influence, inspired by the gardens of the Palace of Versailles, and the waterfall dating from the second half of the 18th century. The various sculptures in the gardens, the painted ceilings and the blue and white tiles stand out.
The main building is of small to medium size, functionally organised around a central corridor and adjacent rooms on the first floor. The support areas were located on the ground floor. Little remains on site of the interior wall coverings on the first floor as most of them fell into disrepair and were stolen (paintings, wall coverings and old tiles). There is a secondary building supporting the main building.
In recent years it has hosted services of the Ministry of National Defense.