Luxembourg (Luxembourgish: Lëtzebuerg, French: Luxembourg, German: Luxemburg), also known as Luxembourg City (Luxembourgish: Stad Lëtzebuerg or d'Stad, French: Ville de Luxembourg, German: Stadt Luxemburg, Luxemburg-Stadt), is the capital city of the Grand Duchy of Luxembourg and the country's most populous commune.
Standing at the confluence of the Alzette and Pétrusse rivers in southern Luxembourg, the city lies in the center of Western Europe, located 213 km (132 mi) by road from Brussels, 372 kilometers (231 mi) from Paris, and 209 km (130 mi) from Cologne. The town comprises Luxembourg Castle, established by the Franks in the Early Middle Ages, around which a settlement developed.
As of 31 December 2019, Luxembourg City has a population of 122,273 inhabitants, which is more than three times the population of the country's second most populous commune (Esch-sur-Alzette). The city's population includes 160 nationalities. Foreigners represent 70% of the city's population, while Luxembourgers represent 30 percent of the population, and the amount of foreign-born residents in town rises steadily each year.In 2011, Luxembourg was rated as having the second-highest per capita GDP in the world at $80,119 (PPP), with the city having grown into a banking and administrative center. In the 2011 Mercer worldwide survey of 221 cities, Luxembourg was set first for personal security, while it was ranked 19th for quality of living.Luxembourg is one of the de facto capitals of the European Union (alongside Brussels, Frankfurt, and Strasbourg), as it is the seat of several institutions, agencies, and bodies of the European Union, such as the Court of Justice of the European Union, the European Court of Auditors, the Secretariat of the European Parliament, the European Investment Bank, the European Investment Fund, the European Stability Mechanism, and Eurostat.