- Built by
- The emperor Zeno
- Period
- 476–490
- Aisles
- Three · six arches on seven columns
- Apses
- Three, sanctuary in the central
- Deviation
- 6 degrees north — about 2.43 m
Of the four wings this is the longest, and it is where the liturgy was celebrated on Sundays and feast days. It is the church in the strict sense; the other three brought people in and held them.
It has three aisles, six arches carried on seven columns, and ends in three semicircular apses with the sanctuary in the central one.
It also has a detail you only see by measuring: the wing, with its apse, deviates six degrees north — about 2.43 metres. A deliberate swerve in a building that is otherwise square to itself.
The central apse is distinguished by the decoration of its great arch, by five windows in a single lower row for light, and by one window alone in an upper row. Above it runs a cornice of large blocks carved as shells or pinecones.
On either side of the three apses are two square chambers: one for service, the other for the keeping of relics — to which a small further room was later added as a storeroom.