Afsluitdijk
Coordinates: 53°00′30″N 5°11′25″E / 53.00833°N 5.19028°E
The Afsluitdijk (Dutch pronunciation: [ˈɑfslœyˌdɛik], Frisian: Ofslútdyk; English: Closure Dike) is a major causeway in the Netherlands, constructed between 1927 and 1932 and running from Den Oever on Wieringen in North Holland province, to the village of Zurich in Friesland province, over a length of 32 kilometres (20 mi) and a width of 90 metres (300 ft), at an initial height of 7.25 metres (23.8 ft) above sea-level.
It is a fundamental part of the larger Zuiderzee Works, damming off the Zuiderzee, a salt water inlet of the North Sea, and turning it into the fresh water lake of the IJsselmeer. The Afsluitdijk was the initial demonstration site for a 130 kilometres per hour (81 mph) speed limit in the Netherlands.
Previous experiences had demonstrated that boulder clay, rather than just sand or clay, was the best primary material for a structure like the Afsluitdijk, with the added benefit that till was in plentiful supply in the area; it could be retrieved in large quantities by simply dredging it from the bottom of the Zuiderzee. Work started at four points: on both sides of the mainland and on two specially made construction-islands (Kornwerderzand and Breezanddijk) along the line of the future dike.
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