For 500 years, beginning in 1050, German kings and emperors ruled from this vast hilltop fortress looming above the city from the northern edge of the Altstadt. The Knights’ Hall and Imperial Hall, with heavy oak beams and frescoed ceilings, evoke all the medieval regal splendor you’d expect from chambers where Frederick Barbarossa relaxed between campaigns to subdue the Italian peninsula. Most telling of the era’s social hierarchy is the Imperial Chapel—actually two chapels, one above the other, so an emperor and his court could worship in the airy, bright upper chapel, while lesser members of his retinue prayed in the dark, dank chamber below. Don’t miss the Deep Well, a 50m-long (165-ft) shaft, dug in the 13th-century when the bastions were built; a camera lowered into the well’s depths dramatizes its invaluable role in providing fresh water during a siege. For an extra euro you can tour the Imperial Castle Museum, filled with shields, armor, and weaponry. (You have to feel sorry for the poor fellows who had to lug such heavy equipment for days across an often hostile countryside.) The castle gardens’ views across the city rooftops might have you agreeing with Martin Luther, who opined that "Nürnberg shines throughout Germany like a sun among the moon and stars."