According to those who were there, Zeppelin was still much of an unknown and played an energetic, no frills set which got them notice for the throngs there to see the headliner (as well as the ire of Who management who needed to get them off the stage due to a curfew at the pavilion). As the The Who played on, the crowds were crashed through the fences and swarmed the facility, burning golf carts and an out building and overwhelming the police and security.
At a time when noise ordinances were not yet enforced, according to some the band was very loud, even on the lawn. As the masses descended towards the stage and hung from the rafters, this show and the infamous Who show one year later caused a rethinking of rock concerts at the facility and a tempering of large draw acts for a few years. Luckily that changed by the early 70's.
Before the encores at a Robert Plant & Alison Krauss concert at Merriweather in early 2011, Plant tells the audience about a phone call he received from former Led Zeppelin tour manager Richard Cole. He was reminded that back in May 1969 Led Zeppelin opened for The Who at the Merriweather Post Pavilion calling the headliners “that band, those miserable bastards,” and there was so much damage caused that night that they had to give their earnings back. This brings great cheers among the crowd to which he cheekily followed up with “And next week, Iron Maiden!”
This recording from that night is supposedly only the second time this song was played live in concert and shows the powerhouse they were to become:
"Whole Lotta Love"
Get the original recording at iTunes - Whole Lotta Love - Led Zeppelin
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