Plokštinė missile base, Lithuania - August 19, 2015: Tourists visit the Soviet-era Plokštinė missile base, now a museum, located in Lithuania’s Zemaitija National Park. The undergound base and its four silos began operation on December 31, 1962, housing Soviet R-12 Dvina ballistic medium-range missiles and their nuclear warheads. Decommissioned in 1974, a Cold War museum was opened at the site in 2012.