The terrain is level except for an extension of the Chiltern Hills in the northwest. The chief streams are the Colne, the Lea, and the Stort, which drain into the Thames. Although one of London's
Home Counties, Hertfordshire is primarily an agricultural region, producing large quantities of wheat and hay as well as dairy products, vegetables, and flowers for the nearby London market. There are diverse industries, such as brickmaking, printing, brewing (especially in Watford), papermaking, and engineering. The county figured prominently in the military history of England, particularly during the Wars of the Roses (see Roses, Wars of the ).
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