Led Zeppelin’s first American concert was December 26, 1968 in Denver at The Auditorium Theater. There was a concert that was already booked, on sale and basically sold out featuring Vanilla Fudge and Spirit, but Zepplin was ready to go! So Atlantic Records asked Vanilla Fudge, both bands label, if they would be willing to have Led Zeppelin open their next five concerts starting with this Denver one. But promoter Barry Fey would not pay anything for the band. He said the show is already sold out