Liège (French pronunciation: [ljɛːʒ]; Dutch: Luik, [lœyk] ( listen); Walloon: Lidje; German: Lüttich; Latin: Leodium; Limburgish: Luuk; Luxembourgish: Léck; until 17 September 1946 the city's name was written Liége, with the acute accent instead of a grave accent) is a major city and municipality of Belgium located in the province of Liège, of which it is the economic capital, in Wallonia, the French-speaking region of Belgium.

The city is situated in the valley of the Meuse River, near Belgium's eastern borders with the Netherlands and Germany, where the Meuse meets the Ourthe. It is in the former sillon industriel, the industrial backbone of Wallonia. The Liège municipality includes the former communes of Angleur, Bressoux, Chênée, Glain, Grivegnée, Jupille-sur-Meuse, Rocourt, and Wandre.

The city is the principal economic and cultural centre of Wallonia. As of October 2011, Liège has 196,496 inhabitants. The metropolitan area, including the outer commuter zone, covers an area of 1,879 km² and has a total population of 749,110 as of 1 January 2008. This includes a total of 52 municipalities, a.o. Herstal and Seraing. Liège ranks as the third most populous city in Belgium, after Brussels and Antwerp, and the fourth municipality after Antwerp, Gent and Charleroi. (note that the size of the municipality can be relatively small compared to the real size of the agglomeration)

A city is a relatively large and permanent settlement. Although there is no agreement on how a city is distinguished from a town within general English language meanings, many cities have a particular administrative, legal, or historical status based on local law.

For example, in the U.S. state of Massachusetts an article of incorporation approved by the local state legislature distinguishes a city government from a town. In the United Kingdom and parts of the Commonwealth of Nations, a city is traditionally a settlement with a royal charter. Historically, in Europe, a city was understood to be an urban settlement with a cathedral.

Cities generally have complex systems for sanitation, utilities, land usage, housing, and transportation. The concentration of development greatly facilitates interaction between people and businesses, benefiting both parties in the process. A big city or metropolis usually has associated suburbs and exurbs. Such cities are usually associated with metropolitan areas and urban areas, creating numerous business commuters traveling to urban centers for employment. Once a city expands far enough to reach another city, this region can be deemed a conurbation or megalopolis.