Lille is a city in the northern part of France, within French Flanders. Positioned along the Deûle river, near France's border with Belgium, …Lille is a city in the northern part of France, within French Flanders. Positioned along the Deûle river, near France's border with Belgium, it is the capital of the Hauts-de-France region, the prefecture of the Nord department, and the main city of the European Metropolis of Lille.