Note: Formerly a fortified settlement located on the small Zoom River, its name means "hills on the border [of the marshes]." Became a lordship in 1287, and was much fortified in the 16th century. Was hereditary fief of the duchy of Brabant, and prospered in the 15th century. Withstood sieges by Parma in 1588 and by Spinola and 1622