Searched for backup and found this - from Las Vegas Weekly - "top 25" concerts held in Vegas
3. Led Zeppelin, Las Vegas Ice Palace, 1969
Though the Internet purports Zeppelin's only Vegas-related date to have been an April 19, 1970, Convention Center cancellation (either Robert Plant was in poor health or tickets weren't selling well, depending which version you believe), we've spoken to a dozen individuals who vividly recall getting the Led out at this once-hopping all-ages venue in the Commercial Center off Sahara Ave. It went down atop the wood-covered ice of a hockey arena—most likely, we deduce, on either August 11 or 12, between shows in San Diego and Phoenix—with fans of the band's blues-driven early music fanning across the plywood floor and up the bleachers along the sides. "They were good, except when Jimmy Page pulled out that violin bow and drove me nuts with it for the next 25 minutes," recalls Las Vegas resident Tom Burt. "It was before they were really big—they only had their first album out—but if you knew what was goin' on, you knew who they were."