Ringvaart

The Ringvaart is a canal in the province of North Holland, the Netherlands. The Ringvaart is a true circular canal surrounding the Haarlemmermeer polder and forms the boundary of the Haarlemmermeer municipality. Ringvaart is also the name of the dike bordering the canal.
Construction of the canal began in 1839 as the first step to reclaim land from Haarlemmermeer . Thousands of laborers dug a canal through the existing land, as much as possible closely following the lake's contour. But at three locations , the Ringvaart was dug through peninsulas which thereafter became part of Haarlemmermeer.

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