Walk round Ascoli Piceno, and in some ways it could be any Italian town. There are two big squares where locals watch the days go by, sit in cafes to people-watch, and do their nightly passeggiata stroll. There are centuries-old churches and even ancient remains dating back to the Roman period.

As in plenty of other Italian towns, the center was constructed in the medieval period. And, just like others, it's been beautifully preserved. But wander round -- especially at night -- and you'll notice one major difference: Ascoli appears to glow.