It took a landslide, in 1845, to bring back to light what was left of the basilica of Santo Stefano: an early Christian building with several naves and adjoining chapels that the ground of Melfi had swallowed. Of that whole complex a single room survives, the end chapel, the one people in Melfi call the Madonna delle Spinelle. The rest is gone: the ruins of the nave were levelled in the seventies to make the forecourt you cross to reach it.
What to see
The chapel has a hexagonal plan and six half-columns set against the walls, rising to carry the cornice: a closed, regular geometry, the opposite of the rough shapes of the frescoed caves on the slopes of Mount Vulture. Those came out of the monastic migration from Asia Minor and the Balkans after the iconoclast struggles of the 8th century; the Spinelle belong to an older season, the early Christian one, and this is the only piece of that architecture still standing.
A long underground tunnel is linked to the structure and, according to local traditions that have been partly confirmed, it ran all the way to the castle. That passage explains why the place served not only for worship but also for meetings and assemblies: whoever came in here could reach the fortress without being seen in town.
Visiting
You arrive from the forecourt built over the remains of the nave and go down to the chapel; the visit is short, because there is only one room. Take your time with it: everything lies in the rhythm of the six half-columns and in the way the rock has been cut. To get a sense of the original size, look at the forecourt, because that whole surface was the basilica. Hours are not fixed, so ask in town before going.
Our editors' tip
Keep one date in mind while you are down there: 1089. That year, at the third of the councils held in Melfi, Pope Urban II called the First Crusade, and tradition has it that the Norman soldiers led by Bohemond of Hauteville set out from this very structure. Then come back up and walk towards the castle: it is the far end of the tunnel that ran under your feet.