La Cour d'Honneur du chateau de Versailles
The model for so many of Europe's palaces.
Cour d'Honneur (French pronunciation: [kuʁ dɔnœʁ], Court of Honor) is the architectural term for defining a three-sided courtyard, created when the main central block, or corps de logis, is flanked by symmetrical advancing secondary wings, containing minor rooms. The Château of Versailles (illustration) and Blenheim Palace (plan) both feature such entrance courts.
Some 16th century symmetrical Western European country houses built on U-shaped groundplans resulted in a sheltered central door in a main range that was embraced between projecting wings, but the formalized cour d'honneur is first found in the great palaces and mansions of 17th century Europe, where it forms the principal approach and ceremonial entrance to the building. Its open courtyard is presented like the classical permanent theatre set of a proscenium stage, such as the built Roman set of opposed palazzi in a perspective street at Palladio's Teatro Olimpico (Vicenza, 1584). Like the theatre set the built environment is defined and enclosed from the more public space by ornate wrought iron gilded railings. A later development replaced the railings with an open architectural columnar screen, as at Palais Royal (Paris), Schönbrunn Palace (Vienna), Charlottenburg Palace (Berlin), Alexander Palace (Saint Petersburg), or Henry Holland's Ionic screen formerly at Carlton House, London - wiki