Селигер
Then during the night on 22 October 1946, a selected group of more than 170 German scientists and engineers - plus equipment - from the Zentralwerke were unexpectedly and forcibly (at gunpoint) moved to the USSR by 92 trains as part of Operation Osoaviakhim with more than two thousand German specialists . From 1946–1950, Gröttrup was in charge of the more than 170 German specialists brought to Branch 1 of NII-88 on Gorodomlya Island in Lake Seliger. The German team was indirectly overseen by Sergei Korolev, the "chief designer" of the Soviet rocketry program.