In 1932, the North Sea coastline of The Netherlands was sealed off by a 30-km (19-mile) dike, connecting the province of Noord-Holland with Friesland. The Afsluitdijk stands 100 meters (328 feet) wide and sits seven meters (23 feet) above sea level, and this outstanding feat of hydraulic engineering closed the mouth of the saltwater Zuiderzee (Southern Sea), shortening the coastline and giving Amsterdam and other low-lying towns protection from repeated flooding by the sea.
In time the Zuiderzee became the freshwater Ijsselmeer – one of the largest lakes in Western Europe – and while large areas of land were reclaimed for farming and housing, many residents of the outlying fishing villages lost their livelihoods. Towns including Volendam, Makkum, Hoorn and Harderwijk turned to tourism for a new lease of life; today the region is a paradise for walkers and cyclists – the 405-km (252-mile) Zuiderzee Cycle Route circles the Ijsselmeer – while the Zuiderzeemuseum at Enkhuizen recalls past times with reconstructed buildings, fishing boats, windmills and displays of traditional Dutch crafts in an open-air museum. Other towns including Medemblik have become top spots for water sports, while former islands such as Marken are now connected to the mainland; its pretty green-gabled village is one of the most popular with visitors to the region.