Soviet Border Troops
In 1952, upon signing the Treaty of San Francisco, Japan renounced its claim to the island. Soviet Border Troops occupied the former Japanese military facilities. As early as the 1950s, a P-14 radar "Tall King" VHF air defense radar existed on the far northeastern tip of Urup Island. The troops were withdrawn upon the dissolution of the Soviet Union in 1991, the co-located airfield was turned into a bombing range. The island is now uninhabited and is administered as part of the Sakhalin Oblast of the Russian Federation.