Gene Simmons Took His Son to See Maiden
Gene Simmons, leader of Kiss, wrote in his latest diary:"Took my son Nick and his friend Alex (producer Giorgio Morodor's son) to see IRON MAIDEN. Maiden were terrific. While I usually get the lion's share of attention in public, going out with my son teaches me a good lesson in humility. Nick stands out in a crowd. He's just under 6 foot, 6 inches tall. Wears a size 15 foot. I'm 6 foot, 2 inches tall. I've always been used to being the big guy. Not around my son. But, being in KISS has its rewards. For one thing, when your son finds another band interesting, you can always say "..oh yeah. We took them out as our supporting act on their first tour in the early '80s (Europe)." It's great to hear him say, "...really? Wow."
Source:GeneSimmons.com
5 Comments
And then we al know who "opened up" for maiden in 88 Monsters of Rock 
Yeah, there are many such curious facts! Motorhead, Judas Priest - in the early days maiden opened for them, but now they open for Maiden! ![lol[1].gif](style_emoticons/<#EMO_DIR#>/lol[1].gif)
Judas Priest doesn't open for Maiden and as far as I know Maiden never opened for Motorhead.
I don't think Maiden has ever opened for Motorhead, but I'm not certain 
Well, Maiden opened for Motorhead in 1979 for a benefit gig in the UK. A year later, in September-October 1980, they opened for Kiss on a small tour. In June and July of 1981, they opened for Judas Priest on the US tour and again in September and October 1982 for their next US tour.
If you count festivals:
Judas opened for Maiden in Germany in december 1983 (along with Ozzy, Scorpions, Def Leppard, Krokus,...).
Motorhead opened many times for Maiden on tours and once in a festival (1996 in Brazil).
As for Kiss, they opened at Donington 88 and at the Monster of Rock gigs in the same year (2 times Germany, once in Holland and once in Italy).
Cheers