The Happy Station Show is the world's oldest international radio programme still being broadcast, having originated in 1928 on shortwave radio. The show followed a format of light entertainment, special guests, music, and information about Dutch life. Later, the show pioneered international call-in shows, in both the English and Spanish versions, during the 1970s. "Happy Station" was PCJJ and then Radio Netherlands Worldwide's most popular programme, claiming an audience of as high as 100 million in the 1930s and 25 million in the 1970s.