The drummer headed to the Lollapalooza travelling rock festival just months after Cobain's death in 1994 as he struggled to come to terms with the loss of his close friend and bandmate.
Grohl was left in floods of tears as his emotions came tumbling out when the crowd broke into a spontaneous rendition of the classic Nirvana track.
He tells Mojo magazine, "After Kurt died, that summer I went to Lollapalooza in Detroit. Nobody ever recognised me back then, and I was sitting in this massive amphitheatre waiting for the next band, in the middle of 30,000 people, and All Apologies came over the Pa. The entire audience started singing along, and I started crying. Because it wasn't that long ago that we had lost Kurt and that album had such an emotional impact on me. It's still hard to listen to it."