With the onset of the eastern front of World War II, 3500 students went to the army and hundreds were involved in constructing fortifications to the university itself. The main building was transformed into a hospital and another building was used as a tank school. Institute shops filled military contracts. On September 8, 1941 the Siege of Leningrad began. Research on the strength of ice by employees S. S. Golushkevich, P. P. Kobeko, N. M. Reyman and A. R. Shulman proved the feasibility of transporting vital materials across ice. The researchers selected the safest route for the Road of Life - the transport route across the frozen Lake Ladoga, which provided the only access to the besieged city.