We were in town for 2 days and mt wife said we had to do this. It was a foggy, damp drizzly day (so not much of a view unfortunately) but I am so glad we did this walk. The Portici is a covered walkway that leads to the top of the hill where the Sanctuary of the Madonna di San Luca is. It goes on for kilometres and is quite impressive. Equally impressive is the amount of steps one has to climb as you leisurely (sort of) ascend. Once you start climbing the hill, it is basically a very long subtle stair case and is a good walk! The views in better weather must be spectacular but it is also a great experience in poor weather as you are outside but covered. Not to be missed in Bologna! PS make sure you are wearing good walking shoes or boots or runners.