Hi there Fredrik
If you want to talk about length... It's a piano piece, not even an orchestral piece, Satie's "Vexations", which was played on the 9th of September of 1963 by a few composers (such as John Cage and Christian Wolff) and performers (such as David Tudor, who was highly associated with John Cage). The performance actually lasted something like 19 hours. Oh, and the Ring is about 15 hours long and is usually spread out in 4 performances of 4 hours each, not played all at once
