If you had access to a time machine, what concerts would you go back to see?

2020 was the first year of my adult life that I did not attend any concerts. I'm sure that I'm not alone in this unfortunate situation. So, this got me thinking about both the concerts that I "missed" (could've gone, but something went wrong) or concerts I "wished I'd had the chance to see."

Plus, I thought this would be a good bookend to the ongoing (and excellent) thread about "the worst concert you ever saw."