City of Luxembourg: its Old Quarters and Fortifications

So formidable were Luxembourg's defences that the city was dubbed the Gibraltar of the North. From the 16th century until the walls came down in 1867, Burgundians, Habsburgs, French, Spanish and Prussians each strengthened the stronghold in turn, boring the famous casemate galleries deep into the sandstone cliffs above the Alzette and Pétrusse valleys. UNESCO inscribed the old quarters and surviving fortifications in 1994, a dramatic collage of ramparts, ravines and old-town streets.