Colonnade
COLONNADE, noun
1. In architecture, a peristyle of a circular figure, or a series of columns, disposed in a circle, and insulated within side.
2. Any series of range of columns.
A polystyle colonnade is a range of columns too great to be taken in by the eye at a single view; as that of the palace of St. Peter at Rome, consisting of 284 columns of the Doric order.