There's a song with a 29-hour duration - Apparently.
The longest song ever recorded is "Longplayer" by Jem Finer, a British musician. Released in 2000, it's a continuous, ever-changing piece of music that will only end when a specific date in 2999 is reached. The song's algorithm ensures that it will evolve over time, incorporating new sounds and melodies, but never repeating itself. A real-time clock on the song's website displays the time elapsed, allowing listeners to experience the gradual changes in the music over the course of years.