Three days will not run out of things to see. The historic centre — built across seven hills and the islands of the Regnitz — is small enough to walk in a long morning, but the layering of medieval, Baroque, and ecclesiastical buildings rewards slow looking. The Cathedral on the upper-town hill, the Old Town Hall perched on its bridge mid-river, the New Residence with its rose garden over the rooftops, and Michaelsberg Abbey on the western height anchor the four corners. In between, Klein Venedig (Little Venice) lines the lower river with half-timbered fishermen's houses, and a dozen working breweries pour Rauchbier into stone-mug-sized glasses.