The windmill in Tündern is a Dutch type ground-sailers. That means, that the sails rotor with a diameter of 25 m reaches almost down to the ground. The mill was built in 1883 at the bank of the river Weser. The mill has a specific feature: the cap of the mill is turnable. With the cap, the mill is able to turn around to face the wind direction. This is an essential requirement for windmills to operate economically in the Weserbergland where wind directions are variable. The eight-winged fan drive, that you see on the photo. delivers the energy to turn automatically the 15 t heavy cap.