There can only be one truly great festival a lifetime and it's
the "Us Festival".

from The Simpsons – Homerpalooza on Rap Genius

Meaning

The US festivals (there were actually two US festivals, presumably Homer only went to one or this is some kind of hidden joke) were a pair of concerts focusing on Rock and Roll. The first was a three day event, the second was split into four sections over four days. Bands that played at the festivals included:

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