This is the town square of Lille. To the right one can see La vieille bourse (the old exchange) built from 1652 to 1653.
The history of Lille is very different than that of the rest of France. It was part of the county of Flandres, and though the count of Flandres officially was a vassal of the French king he had been de facto independent since the 11th century. The county of Flandres later became part of the Burgundian empire, and then of the Spanish Netherlands. In 1667 Louis XIV conquered the city making it a part of France.
The adjective 'Flemish' nowadays has multiple meanings. When in France one speaks of Lille as a Flemish town this adjective has geographical meaning, denoting a small region of France, together or without the Belgian provinces of West and East Flandres, denoting a geographical, and or cultural zone. Outside France 'French Flandres' can point to the French part of this zone, or only to the part of this zone where the Flamish language is spoken. In nowadays Belgium Flemish usually has a linguistic and or administrative meaning, denoting the (administrative) part of Belgium that speaks Flemish (or Dutch), thus including parts of Belgium that have nothing to do with the county of Flandres, and excluding French Flandres.
The Flemish heritage of Lille is still reflected in the architecture of the town, a strong regional culture, Flemish names popping up here and there, regional cuisine etc. With 220,000 inhabitants Lille nowadays is not as big a city as it used to be. This means that the old town is much larger that one would expect of a city of this size. With lots of monuments in a fine state the town is well worth a visit.