From 1965 onwards Kempkens traveled regularly to Prague where he mixed with Czech climber friends he had met in 1964 in the Tatra Mountains. On1 May 1967 he was back in Prague and photographed the 1 May Parade as a reporter. Instead of photos of tanks and marching soldiers his photos showed young soldiers as Blues players as they walked with their girlfriends together in the parade. It was spring in Prague and the young soldiers showed that to them the Prague Spring already lived. A photo was published in the Düsseldorf Nachrichten after his return.