You can easily spend a full day here seeing the sights. Begin at the central market square, Hauptmarkt, the most colorful place in Nürnberg, filled with kiosks stacked tall with fresh produce brought in from the countryside. Nearly all the city's attractions lie nearby within the medieval fortifications, parts of which still remain. Between the main wall (which has rampart walks) and the secondary wall once ran the waters of a protective moat. At the "corners" of the Altstadt are the massive stone towers, still intact, of the city gates. The remains of dozens of other gateway towers still exist along the ramparts. Crowning the northern periphery of the Altstadt is the Kaiserburg.
The best example of Nürnberg's aesthetic passion is the Beautiful Fountain on Marktplatz. This stone pyramid, 18m high (60 ft.), dates from 1396 and is adorned with 30 figures arranged in four tiers. Within it is enclosed the symbol of Nürnberg, the journeyman's ring.
At some point in your day, wander over to Handwerkerhof, near the main train station. In this mall, you can see artisans creating the products for which Nürnberg has been known since the Middle Ages: glassware, pewter (often in the form of beer mugs), intricate woodcarvings, and toys.
If you're interested in a famous landmark of World War II, visit the Justizgebäude, Fürtherstrasse 22 (U-Bahn: Bärenschanze), where the "Judgment of Nürnberg" took place. Here, in room 600, the surviving leaders of the Third Reich stood trial in October 1946 for crimes against humanity. Afterward, 10 were hanged. The building still serves as a courthouse, and you'll have to ask the guard at the door if you can enter.