Spectrum, Philadelphia, U.S.A - 8/2/75
(Rare 8mm footage showing Led Zeppelin playing Rock ‘n’ Roll)

Fights break out during Stairway To Heaven and Robert Plant tries to pacify the situation:

Jimmy Page -"What happened was, somebody [left his seat and] came to the front of the stage to take a picture or something, and - obviously - somebody said, ‘Be off with you.’ And he wouldn’t go. And then one chap [security goon] went over the barrier, and then another, and then another and they all piled on top of…you could see the fists coming out, on this one solitary person. And they dragged him by his hair and were kicking him. It was just sickening."

At that point, an angered Robert Plant stopped singing about a bustle in your hedgerow and began shouting at the goons to stop beating the crap out of this poor stoned kid. The kids up front were screaming at the goons. Jimmy stopped the show and walked around, his guitar hanging, visibly upset. Robert went to the lip of the stage and bopped one of the goons on the head with the base of his microphone stand. These burly shirts turned around and started glaring at Robert, who was trying to restore the stuporlike calm that had prevailed in Philadelphia until then. "Can we advocate that people stay in their seats?" he pleaded. "It’s not very pleasant to see situations like this, right under your nose…so…can we all keep cool?"

The encore was short, and the band was out of the hall and into the cars before the amps stopped buzzing.

Led Zeppelin never performed in Philadelphia again. 

-Excerpt from LZ-75’: The Lost Chronicles of Led Zeppelin’s 1975 American Tour by Stephen Davis

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