Colonnade Colonnade In classical architecture, a colonnade is a long sequence of columns joined by their entablature, often free-standing, or part of a building. Paired or multiple pairs of columns are normally employed in a colonnade which can be straight or curved. The space enclosed may be covered or open. In St. Peter's Square in Rome, Bernini's great colonnade encloses a vast open elliptical space. When in front of a building, screening the door (Latin "porta"), it is called a portico, when enclosing an open court, a peristyle. A portico may be more than one rank of columns deep, as at
Xystus (architectural term) Xystus (architectural term) Xystus was the Greek architectural term for the covered portico of the gymnasium, in which the exercises took place during the winter or in rainy weather, etc. The Romans applied the term to the garden walk in front of the porticoes, which was divided into flower beds with borders of box, and to a promenade between rows of large trees. "Xystus" derives from the Greek word "xustos", meaning "smooth", due to the polished floor of the xystus. "Xystus" was used, by extension, to refer to the whole building containing the gymnasium and portico, as in the xysti