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

Santana @ Woodstock
Rush @ anytime
Pearl Jam @ 2000's
The Who @ early 1970's

How could I forget..
A fine Dylan concert, Emerson Lake and Palmer, Peter Greene with Splinter Group, Dick Dale, 
Jethro Tull, Foghat, Emy Lou Harris, Steve Earl, Cactus Blossoms, Roger Waters, and
finally three years ago a great McCarthy concert.  
Many musical memories.  All fine for different reasons. A young Bob Segar always had everyone on their feet rocking and rolling! 
Also...Freddie Cannon in a small club was superb. 

For the sake of clarity,you can  list anything you want ("no limits"); it doesn't matter if you missed it the first time around or if you would want to revisit a great show that you did attend.

I'm not surprised by the amount of mentions for the Allman Brothers; but, I'm surprised that no one has mentioned the Humble Pie performances at The Fillmore East that became: "Performance: Rockin' At The Fillmore" live album. But, as tempting as that show would be for me, I think I'd go back a year earlier when they were a little hungrier and most importantly still doing both an acoustic & electric set(s).

If you are a fan of the acoustic era Humble Pie, I urge you to seek out an 8 minute live clip from German TV of Humble Pie (YouTube) doing an acoustic cover version of "For Your Love" (Yardbirds). It is fantastic; and, it will surely remind you of how great a singer Steve Marriott was!

Genesis December 18, 1974 at the Century Theater Buffalo NY. We got last minute SRO tickets and sat on the stairs in the balcony. They did The Lamb Lies Down On Broadway from start to finish. Great show at a great venue. A close 2nd would be Paul Simon at the Sony Music Center in Toronto the summer of 2016. I don't know if I ever heard a better sounding or tighter performance. Honorable mention would be the Stones in June of 1975 at the Buffalo War Memorial Auditorium. They hadn't played Buffalo in years and it was pretty wild. I had never seen the Aud as packed as it was that night. Bonus was the Crusaders were the opening act.