The Ralsko Mountain and the airfield were used as a military weapons-testing area for decades. After the Prague Spring of 1968, the installation was manned by Soviet Troops. In the late 1980s the Soviet 442nd Missile Brigade stationed SS-21 short-range tactical missiles at Hvězdov. It 1988, there was more than 20,000 permanent Soviet inhabitants (soldiers and their families) in the area. After the collapse of the Soviet Union in 1990–91 the missiles were withdrawn and the entire weapons-testing area was closed off.