Fans of outdoor activities like Möhnesee. This is an artificial lake that is called the Westphalia Sea for its size. During warmer months, you can swim, boat and sail yachts there, wander through the woods, sit in cafes.
Möhnesee Lake’s main man-made decoration is a huge dam built in 1908-1913. It "became famous" as the scene of one of the most famous operations of the British air force during the Second World War. In 1943, No. 617 Squadron RAF carried out an attack on the dam using "bouncing bombs”. The mass of water thrown out on the surrounding areas, swept away everything on its path killing more than a thousand people in Arnsberg and the surrounding area. These events are recreated in the English film The Dam Busters (1955).