Flanders
Flanders shares its borders with Wallonia in the south, Brussels being an enclave within the Flemish Region. The rest of the border is shared with the Netherlands (Zeelandic Flanders in Zeeland, North Brabant and Limburg) in the north and east, and with France (French Flanders in Hauts-de-France) and the North Sea in the west. Voeren is an exclave of Flanders between Wallonia and the Netherlands, while Baarle-Hertog in Flanders forms a complicated series of enclaves and exclaves with Baarle-Nassau in the Netherlands. Germany, although bordering Wallonia and close to Voeren in Limburg, does not share a border with Flanders. The German-speaking Community of Belgium, also close to Voeren, does not border Flanders either. (The commune of Plombières, majority French speaking, lies between them.)
History of Flanders
The contemporary territory of Flanders (i.e., the Flemish Region as the Dutch-speaking part of the Kingdom of Belgium) contains within it the core of the old county, West Flanders and East Flanders, plus three more provinces to the east which were not originally part of Flanders. These are the provinces of Antwerp and Flemish Brabant which were historically part of the Duchy of Brabant, and the province of Belgian Limburg, which was part of the Prince-Bishopric of Liège. (The city of Brussels, historically part of Brabant, is now politically part of the Flemish Community but not of the Flemish Region.)