https://en.wikipedia.org/wiki/As_Slow_as_Possible

'An organ in St. Burchardi church in Halberstadt in 2001 began a performance that is due to end in 2640. This makes it the longest running non-computerized piece currently being performed. The most recent note was played on February 5, 2024. The next note will be played on August 5, 2026.'