The Haringvliet is a large inlet of the North Sea, in the province of South Holland in the Netherlands. It is an important estuary of the Rhine-Meuse delta.
Near Numansdorp, the Hollands Diep splits into the Haringvliet and the Volkerak estuaries. It is closed off near Goedereede from the North Sea by the Haringvlietdam, which provides a road connection between the island of Voorne to the north and the island of Goeree-Overflakkee to the south. The dam with its sluices was built as part of the Delta Works sea barrier protection works, and allow for a brackish ecological environment.
The Haringvliet estuary contains the island of Tiengemeten, which is separated from the river island of Hoeksche Waard by the Vuile Gat strait.
Coordinates: 51°46′18″N 4°12′57″E / 51.77167°N 4.21583°E