Discover Corte Sgarzerie Cryptoporticus

A small courtyard off a side street, with a brick loggia along one side. Steps lead down from it into a low barrel-vaulted gallery on heavy square piers, built in brick and local stone. The vault is plain, undecorated and lit only by lamps.

A cryptoporticus is not a cellar or a crypt, though it looks like both. It is a piece of Roman civil engineering: a covered arcade, partly below grade, used to retain a slope and create a level platform on top of it.

What survives here is a stretch of barrel-vaulted gallery on heavy piers, in brick and local stone, running beneath the courtyard.

The vaults are plain and structural, with no decoration -- this was never a room to be seen, only a means of holding up the temple terrace above it.

Small openings at the upper level admitted light and air, the standard arrangement that distinguishes a cryptoporticus from a true basement.

Above ground, the Loggia del Mangano and the courtyard's arcades are medieval and later, built for the wool trade with no reference to what lay beneath.

A retaining structure that happens to be a room. The gallery is barrel-vaulted on heavy piers, partly below grade, running along the line of the slope. Filling behind it holds the hillside back; the vault carries the terrace above. The usable interior space is a by-product of the engineering, not its purpose — though Romans used such galleries for storage and for shade.

Vaults do the work. A barrel vault converts the load above into outward thrust along its length, which is why the piers are massive and why the structure could support a temple platform without any of the steel a modern retaining wall would use.

Built to be invisible. The masonry is plain and the finish minimal: this was substructure, never intended to be seen, which is exactly why it shows Roman construction more honestly than a faced monument does.

The temple is gone and its foundation is not. That is the usual pattern — the marble above ground was quarried away, and the unglamorous structure below survived because nobody wanted it.

What is a cryptoporticus? A covered, partly buried arcade used to retain a slope and create a level platform on top. It is civil engineering, not a religious or funerary space, despite the name sounding like one.

Is the Capitolium still there? No. The temple above is entirely gone; what survives is the structure that held up its terrace.

How do I get in? Through the Corte Sgarzerie courtyard off the street. Opening is limited and not continuous, so check before making a special trip.