The Kinderdijk-Elshout mill network is an outstanding man-made landscape that bears powerful testimony to human ingenuity and fortitude over a millennium in draining and protecting an area by the development and application of hydraulic technology. It is located in the north-western comer of the Alblasserwaard. It drained the internal drainage districts of De Overwaard and De Nederwaard until 1950, when the mills were closed. The 19 mills that form this group of monuments are all in operating condition. The Alblasserwaard is bounded by the rivers Lek to the north, Merwede to the south, and Noord to the south. The properties consist of discharge sluices, Water Board Assembly Houses, pumping stations, and brick and wooden mills. Owing to changed technical requirements, the discharge sluices were reduced to two and reconstructed in the mid-1980s.
The Water Board Assembly Houses of De Overwaard and De Nederwaard survive intact. The former was built in 1581 and purchased by the Water Board in 1595 to house the Elshout lockmaster. It was used for several other purposes until 1648, when it became the headquarters of the Water Board. It is a two-storeyed brick structure on a rectangular floor plan with a hipped roof. When it became the Water Board Assembly House the modifications included provision of a meeting room, addition of a stone door-arch decorated with coats of arms of the reeve and board members, new windows, and bedrooms in the attic for members. It underwent drastic alterations in 1918 when the dyke there was raised and widened: 3 m was removed from the front of the house and a new facade built. It was restored in 1981-83. The assembly house of De Nederwaard is a plain rectangular two-storeyed building of the 18th century with a hipped roof. (whc.unesco.org)