WDR 4 is a German public radio station owned and operated by Westdeutscher Rundfunk (WDR) in Cologne, North Rhine-Westphalia. Launched in 1984, it is designed as an entertainment program targeting listeners aged 50 and above. The station originally focused on German Schlager music but transitioned to playing international oldies starting in 2011. As of 2023, WDR 4 boasts over 2 million daily listeners, making it one of the most popular radio stations in Germany. The programming includes a mix of oldies, entertainment shows, and informative content catering to its mature audience. WDR 4 broadcasts commercial-free, providing listeners with uninterrupted music and programming throughout the day.