We sat in the mezzanine level "backstage" behind the band

The Olympia was small and somewhat intimate compared to the large stadiums that Zep eventually played in. We were almost overhanging the stage. Every once in a while, Robert Plant would trend through the cables, look up, part his hair with his hands and acknowledge us sitting in the cheap seats. They played what seemed like an hour and during a break between songs he said, "Good evening." It was then we knew we were in for a good, long night. Jimmy Page at his best. Bonham was a HEAVY drummer, before he was heavy...wore the derby and the white jumpsuit if I recall. After, I had to lead my buddy out the door by the hand (acid casualty).