I wrote that I used part of my time, during my latest stay in Tivoli, searching for traces of the local site of the Institute. I'm not sure if I set myself on the right track. Along one of my daily walks I stumbled upon (or better, under) this kind of inaccessible fortress. It is told to be a nunnery. In my past life in Tivoli I don't remember having seen any nun coming out of it. Facing this side of the building, right over the narrow street passing beneath, a huge ravine that leads down to the gorge carved by the Anio river in the last millions of years.