Flag of Karlsruhe, Germany

Karlsruhe (/ˈkɑːrlzruːə/, KARLZ-roo-ə; US also /ˈkɑːrls-/, KARLSS-; German: [ˈkaʁlsˌʁuːə] ; South Franconian: Kallsruh) is the third-largest city of the German state of Baden-Württemberg, after its capital Stuttgart and Mannheim, and the 22nd-largest city in the nation, with 308,436 inhabitants. It is also a former capital of Baden, a historic region named after Hohenbaden Castle in the city of Baden-Baden. Located on the right bank of the Rhine (Upper Rhine) near the French border, between the Mannheim-Ludwigshafen conurbation to the north and Strasbourg to the south, Karlsruhe is Germany's legal centre, being home to the Federal Constitutional Court, the Federal Court of Justice and the Public Prosecutor General. Karlsruhe was the capital of the Margraviate of Baden-Durlach (Durlach: 1565–1718; Karlsruhe: 1718–1771), the Margraviate of Baden (1771–1803), the Electorate of Baden (1803–1806), the Grand Duchy of Baden (1806–1918), and the Republic of Baden (1918–1945). Its most remarkable building is Karlsruhe Palace, which was built in 1715. It contains the Baden State Museum, the large cultural, art and regional history museum of the Baden region of Baden-Württemberg. There are nine institutions of higher education in the city, most notably the Karlsruhe Institute of Technology. Karlsruhe/Baden-Baden Airport is the second-busiest airport in Baden-Württemberg after Stuttgart Airport, and the 17th-busiest airport in Germany.