Polder at Neßmersiel, Germany, aerial view (2012)

The Zuiderzee in the Netherlands is a Polder. Old land is mostly green, new land is darker in color.

Empoldering is a method of reclaiming land from the sea or from inland lakes, and a way to control floods. Empoldering involves the use of a polder, a piece of land in a low-lying area that has been reclaimed from a body of water by building dikes and drainage canals.