Heerlen The Essential
Called Coriovallum in olden times, this town was a Roman camp located on the road linking Boulogne to Cologne via Maastricht. At the beginning of the 20C, Heerlen was the main centre of the Dutch coal fields which cross the Limburg and extend into Belgium (Maaseik region) and Germany (Aix-la-Chapelle basin). Mining was abandoned in 1975. Since then many industries have set up in the region. Heerlen is also a large trading centre.