The Maeslantkering is a storm surge barrier on the imaginary dividing line between the Nieuwe Waterweg waterway located at Hoek van Holland and the river the Scheur located along the cities of Maassluis and Vlaardingen up to the confluence of the rivers Oude Maas and Nieuwe Maas, Netherlands, 51°57′18.98″N 4°09′49.63″ECoordinates: 51°57′18.98″N 4°09′49.63″E, which automatically closes when needed. It is part of the Delta Works and it is one of largest moving structures on Earth, rivalling the Green Bank Telescope in the USA and the Bagger 288 excavator in Germany.