portico, roofed space using columns or posts, generally included between a wall and a row of columns or between two rows of columns. In Greece the stoa was a portico of the first type; in Greek temples porticoes terminated the front and rear ends of the naos—called pronaos and opisthodome, respectively—and were included in the colonnade surrounding the building. Roman temples, rarely peripteral (surrounded by columns), had a portico at the front end only. Such temples were called prostyle temples; those having porticoes at both front and rear were termed amphiprostyle. The projection of Roman porticoes was generally three columns deep. In recessed porticoes the front colonnade is flanked by the extended side walls of the building, as in most Greek examples.

Colonnaded porch or entrance to a structure, or a covered walkway supported by regularly spaced columns. The portico is a principal feature of Greek temple architecture and thus a prominent element in Roman and all subsequent Classically inspired structures.

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