The Nederwaard Mill is an old water mill in the town of Kinderdijk. It was built in 1738, and is one of eighteen mills in the area. The group of mills in Kinderdijk is the largest group of historic water mills in the Netherlands, and the mills attract around 3 million tourists each year. The Kinderdijk was recently added to the Unesco World Heritage list, because the site is a fine example of a polder with natural drainage, water mills, and a variety of outlets. The Kinderdijk has changed very little since the construction of the first mills, and is one of the last remaining examples of 18th century engineering on such a grand scale.