San Vitale does not look like much from the outside. It is a squat octagon of plain brick, built in the sixth century, and the first reaction of many visitors is mild surprise. Then you step through the door and the interior opens up in layers of marble, arches and light, and the apse is covered in mosaic so bright it seems to glow. It was begun under the Ostrogothic king Theodoric's rule, around 526, and finished and consecrated under Byzantine rule in 547, in the years after Justinian's generals had reconquered Italy.
The two panels everyone comes for face each other across the apse. On one the emperor Justinian stands with his court and the bishop Maximian, carrying a golden bowl; on the other his wife Theodora, in a jewelled crown, sweeps in with her ladies. Neither ruler ever came to Ravenna. They are present by proxy, which was the point: this was Byzantium's statement of power in a recaptured Italy, pressed into glass and gold.
Take your time here, and look at the details: the peacocks, the vines, the lambs. It is a good example of why the monuments of Ravenna are inscribed together, because the building sits next to the Mausoleum of Galla Placidia in a quiet courtyard, so you can visit both in the same short walk.
For riders the connection to the ride list is the Vena del Gesso Romagnola, the long white ridge of gypsum that runs across the Apennine foothills south of Faenza and Imola. The gypsum is the same family of rock that dissolves into caves and sinkholes, and Monte Penzola is a good place to see the stripped, bright slopes. After the dark, glowing interior of San Vitale it makes an interesting contrast: the same pale material that Romans used for plaster, still lying in the open.
Parking in Ravenna's historic centre is restricted, so use the car parks on the edge and walk the few minutes. The town has plenty of fuel on its outskirts, and the cafes around the Piazza del Popolo make a pleasant place to sit and wait for the queue to ease, which in high season it must.