This is an astonishing subterranean site of around 20 ancient rooms, many adorned with original frescoes. The rooms were used as shops or storage units until the 3rd century CE, when they were transformed into a domus (house). According to tradition, two Christian Roman soldiers, John and Paul, lived here before they were martyred by the emperor Julian. There’s no direct evidence for this, although research has revealed that the houses were used for Christian worship.
Entry to the case, which lie beneath the Basilica dei SS Giovanni e Paolo al Celio, is on the Clivo di Scauro, a picturesque Roman road spanned by a series of medieval arches.