Knokke-Heist is a municipality in the Belgian province of West Flanders. The municipality comprises the towns of Heist-aan-Zee, Knokke, Duiā¦Knokke-Heist is a municipality in the Belgian province of West Flanders. The municipality comprises the towns of Heist-aan-Zee, Knokke, Duinbergen, Ramskapelle and Westkapelle. On January 1, 2006, Knokke-Heist had a total population of 34,063. The total area is 56.44 km² which gives a population density of 603 inhabitants per km². Knokke-Heist is located along the North Sea in a polder area on the Belgian border with the Netherlands. It is Belgium's best-known and most affluent seaside resort.