The former “Silk Flowers Nunnery” is now a retreat as refined as the name implies. Enough of the 14th-century surroundings remain to remind you where you are—a crucifix looms over the chic balcony breakfast room, fresco fragments and exposed timbers offset crisply contemporary furnishings and lots of high-tech lighting and gadgetry, and curved walled, double-height rooms are cleverly carved out of the former chapel. But the emphasis is clearly on worldly comforts that include fine linens, luxurious, mosaic-tiled bathrooms, and a little spa where guests can soak and steam after a day of sightseeing.