Overwaard Windmill No.4 houses the third museum at Kinderdijk. Yet, the Overwaard Museum Mill is only accessible by boat and is open on a limited basis. This windmill had the one-of-a-kind capability of pumping water in two directions thanks to a pair of massive scoop wheels. One of these wooden wheels weighs nearly nine tons! Overwaard Windmill No.4 (nicknamed Contra Mill) is located at an elbow in the canal. This position provides the most photographic view of the famous Kinderdijk windmills lined up in either direction.