Getting to know Salzburg is not too difficult, because most of its sights are within a comparatively small area. The Altstadt (Old City) is a compact area between the jutting outcrop of the Mönchsberg and the Salzach River. The cathedral and interconnecting squares surrounding it form what used to be the religious center, around which the major churches and the old archbishops' residence are arranged (note that entrance into all Salzburg churches is free). The Mönchsberg cliffs emerge unexpectedly behind the Old City, crowned to the east by the Hohensalzburg Fortress. Across the river, in the small area between the cliffs of the Kapuzinerberg and the riverbank, is the Steingasse, a narrow medieval street where laborers, craftsmen, and traders served the salt-mining industry and travelers coming in and out of the region’s important mercantile hub. Northwest of the Kapuzinerberg lies Mirabell Palace and its manicured gardens.
It's best to begin by exploring the architectural and cultural riches of the Old City, then go on to the fortress. Afterward, cross the river to inspect the other bank. Ideally, you need two days to do it all. An alternative, if you enjoy exploring churches and castles, is to go directly up to the fortress, either on foot or by returning through the cemetery to the funicular railway.