I made a last-minute decision to visit Crespi d'Adda because I had arrived quite early in Milan from Modena and had a few hours to spare before my flight home from Malpensa. It took me quite a long time to get there because it was a Sunday and the buses only go once an hour from outside the Gessate Metro Station. From Trezzo sul Adda, it is quite a long, but reasonably pleasant walk to the site - you can download a map from the site of Crespi's tourist office. I only had about 30 minutes or so before I had to take the next bus back, so I could only take a quick look around, but I had the impression that this was sufficient. There is really not a whole lot to see, just a few private and public buildings, and not much in the way of signage or explanations. The factory and the church are somewhat impressive (as is the owner's villa in the park that can be glimpsed through the trees), but nothing really special. I guess Crespi's inscription is justified because of its value as a company town, but from a tourist perspective, it doesn't offer very much (and on a Sunday afternoon, the place was practically dead).