Afsluitdijk

The Afsluitdijk is a 32-kilometer-long dam and road in the Netherlands that closes off the Zuiderzee from the North Sea, creating the freshwater lake known as the IJsselmeer. It links the provinces of North Holland and Friesland, running from Den Oever on the North Sea coast to Kornwerderzand on the IJsselmeer side. By turning a saltwater inlet into a large inland lake, the dike facilitated land reclamation and expanded agricultural and urban development in the surrounding polders.

Construction of the Afsluitdijk began in 1927 and was completed in 1932 as the centerpiece of the Zuiderzee Works, a large public works program aimed at flood prevention, land reclamation, and improved water management. The structure is built to withstand major North Sea storms and serves as a critical flood defense. Its crest today carries the A6 motorway and a dedicated bicycle path, with access and maintenance facilities at both ends.

In the 21st century, the Afsluitdijk underwent a major modernization to strengthen flood defenses and improve traffic safety while preserving its functional role. Upgrades included reinforcing the dike crest and widening the roadway to separate motor traffic from vulnerable areas; these improvements were completed in the early 2020s.

The Afsluitdijk remains a prominent symbol of Dutch hydraulic engineering and a key link between the mainland and the former Zuiderzee. It forms a central part of the Zuiderzee Works and is associated with the broader Delta Works flood-control system.