The Royal Alcazar of Madrid ("Real Alcázar de Madrid") was a former royal residence. It was originally built as a fortress by Muslims between 850 and 856 AD. It was in the center of Madrid and served as the center of the Spanish royal court. This was up to the construction of the Royal Palace of Madrid by the Bourbons in the 1700's. the great building kept its original title of "Alcázar" (English: "fortress").