Luxembourg (/ˈlʌksəmbɜrɡ/ luks-əm-burg), officially the Grand Duchy of Luxembourg (Luxembourgish: Groussherzogtum Lëtzebuerg, French: Grand-Duché de Luxembourg, German: Großherzogtum Luxemburg), is a landlocked country in western Europe, bordered by Belgium, France, and Germany. It has two principal regions: the Oesling in the North as part of the Ardennes massif, and the Gutland ("good country") in the south. Luxembourg has a population of over half a million people in an area of approximately 2,586 square kilometres (998 sq mi). A representative democracy with a constitutional monarch, it is ruled by a grand duke. It is now the world's only remaining sovereign grand duchy. The country has a highly developed economy, with the world's highest GDP (nominal) per capita according to the IMF. Its historic and strategic importance dates back to its founding as a Roman era fortress site and Frankish count's castle site in the Early Middle Ages. It was an important bastion along the Spanish Road when Spain was the principal European power influencing the whole western hemisphere and beyond in the 16th–17th centuries.Luxembourg is a member of the European Union, NATO, OECD, the United Nations, and Benelux, reflecting the political consensus in favour of economic, political, and military integration. The city of Luxembourg, the largest and capital city, is the seat of several institutions and agencies of the EU.Luxembourg culture is a mix of Romance Europe and Germanic Europe, borrowing customs from each of the distinct traditions. Luxembourg is a trilingual country; German, French and Luxembourgish are official languages. Although a secular state, Luxembourg is predominantly Roman Catholic.