Luxembourg City is one of Europe's great surprises: a tiny capital built on dramatic sandstone cliffs, with a medieval fortress carved into the rock and a leafy river valley curling beneath it. The old town and its ramparts are a UNESCO World Heritage Site, and the view from the Chemin de la Corniche, often called the most beautiful balcony in Europe, sells the place in a single glance.

For centuries this was one of the most heavily fortified points on the continent, fought over by Spanish, French, Austrian, and Prussian powers before its defenses were largely dismantled in 1867. What remains is a city of two levels: a polished upper town of palaces, banks, and squares, and the lower-lying Grund and Clausen quarters along the Alzette, all stitched together by lifts, footbridges, and serpentine staircases.

Today it is a small, safe, multilingual, and remarkably international place where French, German, and Luxembourgish all share the street signs, and where you can walk from a Michelin-starred dining room to a casemate tunnel in fifteen minutes. It is compact enough to see in a weekend but rewards a slower pace.