Thanks PghBaldy. There's at least a couple of recent (2009, maybe one in early 2010) books out about the wartime efforts by Italian authorities to stash loads of art masterpieces in heavily built medieval fortresses, palaces, and monasteries etc, to protect them from bombing. The US military actually had an office (made up of recent college grads who'd studied Renaissance art and so on) that had as its job the protection of various structures and treasures. In at least once case, a renaissance-era palace lavishly decorated inside with magnificent frescoes was thoroughly photographed not long before it was blown to bits in the Italian campaign. Anyway, not long ago I started one of the titles, and didn't get very far into it, then it had to go back to the library. Let's see if I've got the info saved... ah!