I agree, the 70s was the best decade for rock, by far! Everything after it has been an off-shoot.

Damn rundogdave, what a great show! I googled some video of that show, Wolfgang's Vault is all of Bill Graham's archives from Bay Area shows over the years and it's all available online, here's a clip.

wildwoman1313 there's a total running through the turnstiles shot at the beginning of this vid:
http://www.wliw.org/productions/performance/wolfgangs-vault-presents-day-on-the-green-1977/697/

Zeppelin at 8:00, awesome audience shot:
http://www.youtube.com/watch?v=uR5UJULimAU

Other amazing 'from the board' recordings here at Wolfgang's Vault:
http://www.wolfgangsvault.com/concerts/

They also sell original vintage, unsold tee shirts from some of the shows (but they're BUCKS!)