Operations Grouse, Freshman & Gunnerside: The Heroes of Telemark Anniversary Tour 21-23 February 2020, £599 plus £75 per night single room supplement, where applicable. Places available. The Norwegian heavy water sabotage was a series of operations undertaken by Norwegian saboteurs during World War II to prevent the German nuclear weapon project from acquiring heavy water (deuterium oxide), which could have been used by the Germans to produce nuclear weapons. Between 1940 and 1944, a sequence of sabotage actions, as well as Allied bombing, ensured the destruction of the plant and the loss of the heavy water produced. These operations—codenamed Grouse, Freshman, and Gunnerside—finally managed to knock…