Largest flood defence project

According to Official Guinness Records,

The Delta Works, off the coast of Holland, are a huge series of dams, locks, sluices, storm surge barriers and dykes designed to protect low-lying areas of the country from the sea. Construction began in 1950 and ended in 1997 with the completion of the Maeslantkering and the Hartelkering barriers. The Delta Works contain some 16,495 km (10,250 miles) of dykes and around 300 separate structures.
The largest signal component is the Oosterscheldedam, which is the largest single tidal barrier in the world, at 9km (5.59 miles) in length.

For a complete list of Unknown date records, please visit Unknown date Guinness Records in Netherlands.

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