World's slowest concert nears 4% completion after 25 years

An organ in Halberstadt, Germany, has been playing John Cage's 'ORGAN²/ASLSP' since 2001, with a rare chord change marking about 4% completion of the 639-year piece. The performance, which began on Cage's 89th birthday, is scheduled to finish in 2640. The project has transformed the medieval Burchardi Church, drawing visitors to experience its evolving sound.