Flemish Diamond

The Flemish Diamond (in Dutch: Vlaamse Ruit) is the Flemish reference to a network of four metropolitan areas in Belgium, three of which are in the central provinces of Flanders, together with the Brussels Capital Region. It consists of four agglomerations which form the four corners of a diamond shape: Brussels, Ghent, Antwerp and Leuven. Over five million people live in this area, with a population density of more than 800 per square kilometre.

There is no national or federal concept or recognition of a poly-centric conurbation in Belgium that consists of Brussels and any of the other major Belgian metropolitan areas that are relatively proximate to the national capital (lie within a radius of approximately 50 kilometres (31 mi) around Brussels). The matter is the exclusive competence of the regional authorities, and as such, the autonomous Flemish government developed the geographic and socio-economic concept of Vlaamse Ruit or "Flemish Diamond" in the 1990s. The Francophone counterpart is the Triangle Wallon ("Walloon Triangle"), consisting of Brussels and three Walloon metropolitan areas, namely Mons, Charleroi, and Namur.

The distance from Antwerp to Brussels is approximately 51 km (32 mi). The city of Mechelen is in the middle, and towards Brussels the industrial area of Vilvoorde. With the Port of Antwerp stretching to the north, this has long been recognized as a major north-south urban and industrial axis. The western triangular area of the larger cities of Antwerp-Brussels-Ghent comprises the cities of Lokeren located west of Sint-Niklaas, Dendermonde north of Aalst as well as the industrial area Boom – Willebroek, and is generally slightly less urbanized. Such may also be true for the smaller eastern Antwerp – Brussels – Leuven triangle, comprising the city of Lier.

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