In 1964 "Plymouth Rock" made two Caribbean cruises and then took part in Operation Steel Pike I off the coast of Spain, the largest amphibious operation since World War II. Early 1965 found "Plymouth Rock" on another Caribbean cruise. From 28 January to 7 March 1966 she was involved in H-Bomb recovery operations off Palomares, Spain following the Palomares hydrogen bombs incident. Late 1966 found her once again in the Caribbean, providing for the victims of Hurricane Inez in Haiti. After three Caribbean cruises in early 1967, "Plymouth Rock" deployed to northern Europe. She made two more Caribbean deployments in 1968. From June to July 1969 she again deployed to northern Europe.