The "Kresty" was a prison complex opened in the 30's of the 18th century. A "Sharashka" (a research and development facility called OKB-172 that used inmates as weapons engineers and researchers) stood on the grounds of the prison. The facility developed torpedo boats that were widely used by the Soviet Navy during the Great Patriotic War (1941-1945). Many inmates were placed in penal military units or evacuated to the east during the Siege of Leningrad (1941-1944). German POW's were imprisoned in this complex in the last phase of the siege. A large number of inmates and guards died due to starvation.