Enjoy panoramic city and vineyard views from this hulking fortress whose construction was initiated around 1200 by the local prince-bishops who governed here until 1719. Dramatically illuminated at night, the structure was only penetrated once, by Swedish troops during the Thirty Years' War, in 1631. Inside, the Fürstenbaumuseum (closed November to mid-March) sheds light on its former residents' opulent lifestyle, while the Mainfränkisches Museum presents city history and works by local late-Gothic master carver Tilman Riemenschneider and other famous artists.
The fortress is a pleasant 25-minute walk uphill through the vineyards from the Alte Mainbrücke via the Tellsteige trail.