Concierge.com's insider take:
Good hotels in the old part of town are scarce, so if you want to stay down by the river, this is the place. In fact, the Pestana may be the nicest hotel in Porto. Most rooms have panoramic water views (request when you book, just in case) and balconies where you can spend hours gazing upon the harbor and the sights of the downtown Ribeira neighborhood. The hotel is a sensitive fusion of 11 separate riverside town houses spanning the 16th to 18th centuries, plus a sizable slab of medieval city wall. The place is well run, comfortable, and stylish without, thankfully, appearing too "designer."