Windmills Kinderdijk, Holland, UNESCO World Heritage Site - 3644
A polder is a low-lying tract of land enclosed by embankments known as dikes, that forms an artificial hydrological entity, meaning it has no connection with outside water other than through manually-operated devices. There are three types of polder: * Land reclaimed from a body of water, such as a lake or the sea bed. * Flood plains separated from the sea or river by a dike. * Marshes separated from the surrounding water by a dike and consequently drained.
The Windmills at Kinderdijk, the Netherlands are an UNESCO World Heritage Site.