Due to its large number of water sports facilities, a fleet of passenger ships, the rich fish population and numerous sights, the ‘Edersee’ (Lake Eder) has become an attraction for visitors from near and far.
The Eder River originates on the hillside called ‘Ederkopf’ in Westphalia and enters the ‘Waldeck-Frankenberg’ district near Hatzfeld. In narrow loops, the river bed winds its way past towns towering over the valley until it reaches the ‘Frankenberger Bucht’ at Battenberg.
The slopes of the valley section downstream from Herzhausen – filled with the water accumulated by the dam – are characterized by dense forests.
Once upon a time, the Eder flowed in numerous turns through the sometimes narrow, sometimes broad valley, passing Schloss Waldeck through the ‘Uhrepforte’, a natural gorge now closed by the dam. As the streaming river turned into a quiet reservoir, a considerable section of the Eder valley and its villages were submerged by water.
Steep slopes have turned into new shores, narrow side valleys into tranquil bays, rocky heights into bizarre headlands. It is only downstream from the ‘Affolderner See’ (Lake Affoldern) beneath the retaining wall that the Eder reappears as a river and finds its way to the Fulda River. The reason for the construction of the Eder River Dam (1908 to 1914) was the necessity to create a major reservoir for supplying the Midland Canal.
Since 1960, the water supply has been primarily directed at the needs of the navigation on the upper Weser River. The curved gravity dam protrudes from the landscape with a height of 48 m and a length of 400 m at the crown as well as 270 m on the bottom of the valley. This construction resulted in an artificial lake that is 27 km long and has a volume of 202 million m³ of water, a shore length of 69 km and a water depth of up to 42 m. It measures 1,000 m at the widest point and 175 m at the narrowest point. With a volume of 5.4 million m³ and maximum water surface of 180 hectares, the Affolderner See offers leisure and recreation opportunities along its shores.
Due to rapidly changing water levels, bathing is dangerous and thus not permitted. Breeding and resting waterfowls are the reason why the entire basin has been designated as a nature conservation area.