By 1889, Fort Pospelov had been built on the island as part of the Vladivostok Fortress complex, as developed by Colonel K. I. Velichko. Over several years, the initial temporary wooden structures were gradually replaced with stone structures. Fort Russky was built on Russky Mountain, near the highest point on the island, between 1898 to 1903. The fort was built in an irregular trapezoid shape, with numerous artillery batteries which were meant to be able to fire into almost all the bays of Russky island in case of invasion. During the Soviet era the island was a closed territory and was home to several military installations, and became one of the largest training areas for the Soviet Navy.