"1971" . . "The Haringvliet sluices are a construction that closed off the estuary of the Haringvliet as part of the Delta Works. The structure consists of 17 sluices, several kilometres of dam and a shipping lock.Building started in 1957 and was finished in 1971."@en . "56.5"^^ . . "N57" . "Haringvlietdam"@en . "1971Z"^^ . "1958" . . . "56.0"^^ . "5000.0"^^ . "1971-11-15Z"^^ . . "17"^^ . . . .