At Hadrian's Villa, a Marble Slab Still in Its Place Marks Where Lightning Struck at Night and the Ground Became Sacred

The excavation director, Fabio Giorgio Cavallero, said the discovery "opens new perspectives" on this part of the villa and on the role of ritual in how the space was reorganised, and that the stratigraphy would clarify "the sequence that led to the transformations of the whole monumental area". Alberto Samonà, who directs the institute, said the find "shifts attention from grand architecture to the more intimate sphere of Roman religiosity", and the minister, Alessandro Giuli, called it "a rare testimony and extraordinarily evocative".

What we know of the rite

Most of what survives about fulgur conditum is in the texts and in a few finds. The best-known is a statue: in 1864, workmen near the Campo de' Fiori in Rome uncovered a gilded bronze Hercules, now in the Vatican, buried under a travertine slab cut with the letters F C S, fulgur conditum Summanium, with the remains of a lamb beside it. The statue had been struck, and rather than melt it down the Romans buried it as the god's property. More recently, the sanctuary at Bagno Grande in San Casciano dei Bagni, in Tuscany, produced a small bronze lightning bolt deposited with a flint arrowhead, which Giuli cited on Thursday as another material trace of the same idea. The Tivoli slab adds something neither of those has: the structure it was set in, and the layers around it, which can be dug.

Why at the villa

Hadrian built the villa in the early second century, a small city of baths, libraries, theatres and water gardens spread over more than a hundred hectares below Tivoli, and it has been a World Heritage Site since 1999. It was struck by lightning then as it is now; the hills east of Rome take summer storms. What the slab records is that when a bolt came down at night somewhere near the Amphitheatre, whoever was responsible for the place did the correct thing, and did it permanently enough that the marker outlasted the villa. Cavallero's point about reorganisation is the interesting one. A bidental could not be built over, so a strike could change the plan of a district. If the excavation can show that the layout around the Amphitheatre bends to accommodate this spot, the two words on the slab will have explained something about the architecture as well as the religion.

The area will remain under excavation, and the ministry has not said whether the slab will be visible to visitors. Given that its whole value lies in staying where it is, one hopes the answer is a viewing platform rather than a museum case. The Italian coverage, including the full text of the ministry's statement, has more detail than has yet appeared in English.