LIMBURG, or LIMEOURG  , the smallest of the nine provinces of Belgium, occupying the north-east corner of the kingdom . It represents only a portion of the ancient duchy of Limburg (see above) . The part east of the Meuse was transferred to Holland by the London conference, and a further portion was attached to the province of Liege including the old capital now called Dolhain . Much of the province is represented by the wild heath district called the Campine, recently discovered to form an extensive coal-field . The operations for working it were only begun in 1906 . North-west of Hasselt is Beverloo, where all the Belgian troops go through a course of instruction annually . Among the towns are Hasselt, the capital, St Trond and Looz . From the last named is derived the title of the family known as the dukes of Looz, whose antiquity equals that of the extinct reigning family of Limburg itself . The title of duc de Looz is one of the four existing ducal titles in the Netherlands, the other three being d'Arenberg, Croy and d'Ursel . Limburg contains 603,085 acres or 942 sq. m . In 1904 the population was 255,359, giving an average of 271 per sq. m .