A lot has changed about metal concerts over the years: Shaggy manes and thick facial hair gave way to mullets and Aquanet-sprayed dos before going back to shag and beards. Bell-bottoms gave way to spandex and leather before ripped jeans replaced acid-wash.

Some things have never changed, though: Devil-horn hand gestures are still raised high in the air, women's restroom lines are still usually short, and the Twin Cities is still a major market for heavy-metal concerts.

This summer will be the busiest one in recent memory for Minnesota headbangers. The action kicks off next week with the return of Tool to Xcel Energy Center as well as two guaranteed-fun outdoor shows by Alice Cooper. Iron Maiden plays its first Minnesota show in 16 years the following weekend, June 16, also at Xcel Center. Then comes the July 30 reunion show by Guns N' Roses at U.S. Bank Stadium, which looks to be the biggest concert of the summer, period, based on ticket sales.

The buzz for these classic acts got us reminiscing about the even more legendary shows they and many other metal heroes played here in decades past. Here are the concerts that stand out in Twin Cities metal history.

1. Guns N' Roses & Metallica (Metrodome, Sept. 15, 1992)

There are more storied GNR shows, and much better Metallica performances (see below). Combined, though, metal concerts really don't get any bigger than this one — starring two of the genre's top-selling groups, then at their commercial peaks and seemingly thumbing their noses at the grunge bands that were ruining all the fun for '80s metal acts.

Adding to the mythos was the show's likelihood of being called off. Ads for the gig even taunted, "They said it wouldn't happen." Axl Rose had postponed it by a month due to vocal-cord damage. Then Metallica frontman James Hetfield's hand was severely burned by their arsenal of pyro a month earlier in Montreal — this was also the show where a riot broke out when Rose, too, left the stage early, making fans wait three hours between bands.

Amazingly, though, the Minneapolis show came off fairly well. Metallica played a full 2 ¼-hour set with John Marshall of Metal Church capably filling in Hetfield's guitar parts. Rose was in strong voice again as GNR went on at 10:45 p.m., after only a 95-minute wait; which was about how long it took a fan to navigate the Dome's notoriously cramped hallways to get a beer.

2. Led Zeppelin (Met Center and St. Paul Civic Center, April 12-13, 1977)

Not only were these the last Minnesota appearances by the metal gods, they also marked the only time a band of that stature was known to perform one night in Bloomington and then make crew members load everything up and out just to perform 10 miles away in St. Paul — a totally nonsensical, Spinal Tap-ian move. "I think they did it just to say they did it," recalled promoter Randy Levy of Schon Productions (now Rose Presents).

Touring behind their jammiest album, "Presence," the band played nearly the same three-hour set list each night, saving "Stairway to Heaven" and "Rock and Roll" for the end. However, the performances were quite different in quality. The band's private plane was late getting in and delayed the Met Center show by about 75 minutes, which may explain why that's said to be the inferior gig. "We had no frame of reference other than the movie ["The Song Remains the Same"], and they were the biggest thing in our world, so we were happy," said Dirty Frames drummer Michael Reiter, who attended both nights.

On stage the next night, Robert Plant snarkily referred to Jon Bream's slagging review for the Minneapolis Star, which said the band "never seemed to get on track." Bill Lindsey of the veteran local metal group Impaler attended the second night and thinks there's a simple explanation for why it was better: "St. Paul was always more a metal town."

3. Iron Maiden, Ratt, Accept and Mama's Boys (Trout Air Amphitheater, June 23, 1985)

Anyone looking for a local version of the documentary "Heavy Metal Parking Lot" — featuring mullet-haired, boneheaded fans partying outside a Judas Priest concert in 1986 — would have found it here. Trout Air was an early, flimsy attempt at a permanent outdoor music venue in Forest Lake, housed next to man-made fishing ponds on the grounds of what is now Running Aces Casino & Racetrack. "Not surprisingly, the bugs were horrendous," promoter Levy recalled.

Fans recall it being an especially hot day. The heat and the day's high beer sales meant a lot of passed-out fans. It also meant an inordinate number of women going topless. "I recall seeing lots of boobs," quipped Rocket Club drummer Billy Thommes, among the many impressed junior high school boys in attendance, who also remembered, "Every band killed it."

Maiden was touring behind its album "Powerslave" and brought an ancient Egypt-inspired hi-fi production. Ratt had enjoyed mass radio and MTV success a year earlier with "Round and Round," and had the crossover sex appeal sorely lacking in the other bands (especially Accept). "I remember having a blast," is how Kathy Lawrence of Mounds View put it.

4. Rage Against the Machine (Target Center, Sept. 3, 2008, Republican National Convention)

A sharp contrast to the big-dumb-fun aspect of some of these other shows, this one was unequivocally serious, political and impassioned. But if headbanging, fist-pumping and lyric-screaming are hallmarks of a metal concert, it topped most of the competition in voracity.

The Los Angeles quartet returned from an eight-year hiatus to play this quickly sold-out show and another one a week earlier during the Democratic National Convention in Denver. Each member took the stage in Guantanamo Bay-inspired prison garb and played the first song, "Bombtrack," with black hoods covering their heads. Talk about skills to pay the bills.

The night's intensity didn't end with the performance, as concertgoers exiting the show were greeted by hundreds of law-enforcement officials in riot gear. Talk about overreaction. Fans were mostly just interested in expressing their freedom to grab a post-show beer, though, and little happened with the crowd.

5. Monsters of Rock (Metrodome, July 13, 1988)

It was only the second performance in town by Van Halen with replacement singer Sammy Hagar. It was one of the last local shows of the heyday-era Scorpions, who consistently put on mighty performances here. What everyone seems to remember most about this day, though, was how a good chunk of the 35,000 fans showed up early and went crazy for the second act of the five-band lineup.

"I didn't even know much about Metallica at that point, and it was clear as day they had stolen the show," said KQRS-FM jockey John "Johnny Rock" Lassman, who broadcast live from the Dome that day and even remembers feeling bad for the act that had to follow Metallica: "Alone Again" hitmakers Dokken. "People were throwing stuff at them, so much so they abbreviated their set."

6. Ozzfest/Warped Tour (Float-Rite Park, July 18, 1998)

It was the one and only time these two beloved festival tours paired up for a one-ticket event, but it also stands out as one of the best lineups of Ozzy Osbourne's namesake summer event, with Tool, Motörhead, Megadeth and Iowa upstarts Slipknot also in tow. Oh, and Limp Bizkit, too. But the addition of the punky Warped Tour — with Bad Religion, Rancid, NOFX, etc. — complemented the mayhem greatly. "Skatin' With Satan" was a catch line adopted by organizers, who picked the amphitheater in Somerset, Wis., simply because their routing itineraries crossed there.

It turned out to be the highest-attended show ever at Float-Rite, with six stages and 38,000 fans — still the attendance record at the current-day Somerset Amphitheater — and it became a nationwide news story from MTV to Rolling Stone. "The number of bands was so overwhelming," remembered David Connor of St. Paul, now a public defender. Mostly, though, the one-time twofer is simply remembered as a very good time. "Everybody involved just really, really loved it, from the bands and their crews to the fans," local promoter Levy recounted.

7. Alice Cooper (St. Paul Civic Center, April 28, 1978)

Even Mr. Cooper himself remembered this as a legendary show when we spoke to him in 2013, though for a "truly horrible" reason. Said the metal pioneer, "Afterward, we printed up T-shirts for the whole crew that read, 'I survived St. Paul.'"

The show went great up until the encore, with then-new theatrics like the guillotine that enraptured teenage fans like Soul Asylum's Dave Pirner. Just as the band came back and launched into "School's Out," however, one still-unidentified bozo in the crowd threw a tear-gas can at the stage, which halted the show and left a few dozen fans to be treated by EMS crews. "Everybody thought it was actually a part of the show," Cooper recalled, "as if we'd do something that stupid and crazy. We could barely finish the song — or breathe."

In a recent interview with TPT's "Lowertown Line," Pirner remembered, "All of a sudden I noticed 10,000 people running at me, and it was terrifying. I thought that's the way concerts went: Crazy things happened, and everybody got tear-gassed."

8. Kiss and Judas Priest (Met Center, Sept. 28, 1979)

Never mind their disco hit that year, Kiss still oozed fire and blood on the Dynasty Tour, which would be the last with the four original members for two decades and floundered financially because of its bloated stage production. "They always wanted the biggest and the best, and that was the biggest at the time," said Randy Levy, also this gig's promoter. It was also many Twin Cities metalheads' introduction to the opening act, then readying their breakthrough LP "British Steel."

The show might be best remembered as many rock fanatics' gateway drug. Among the preteen fans there for their first concert were the writer of this article (thanks, Dad!), plus David Connor of St. Paul ("I am certain it is the reason that almost 40 years later I still see live music") and future Flipp band member Kii Arens, whose older brother and bandmate Brynn lost track of his sibling during the opening act. "His first rock concert ever, and he lost his mind and ran to the front row," Brynn remembered. "Kii has been a giant Priest fan ever since."

9. Tool on Harriet Island (June 23, 2012)

Officially part of Live Nation's one-and-done River's Edge Festival, this still felt very much like Tool's own concert — the biggest and wildest of the L.A. prog-metal favorites' consistently well-remembered local gigs. About 25,000 fans enjoyed the band's only show that summer, and a rare chance to see them outside on a gorgeous night, something that even black-T-shirted metalheads enjoy.

The surrounding cityscape seemed to enhance the group's hi-fi visual production, as did the chance to smoke pot freely for many fans. They played "Stinkfist" three songs in as the sky drew dark, and the show just kept crescendoing from there.

10. Metallica, W.A.S.P. and Armored Saint (First Avenue, Feb. 6, 1985)

While the MTV-buoyed hair bands of the era often went straight to playing arenas, First Ave became a hub for the thrashier, uglier groups of the day, also including Motörhead, Anthrax and Slayer. Metallica drummer Lars Ulrich said backstage at U.S. Bank Stadium last summer, "Back then, there were certain pockets in the middle of the country that were more progressive and more ahead of the curve musically, and this was one of the big ones. That venue was a big reason why."

The band started off the day very humbly, signing autographs at the Northern Lights record store in St. Paul. "I remember Cliff Burton complaining he didn't like how he looked in the photo they gave us to have signed," Bill Lindsey of Impaler recalled of the band's bassist, who died in a bus crash a year later.

Come showtime, W.A.S.P. had the grander production, with costumes and pyro. Metallica looked like dull joe-blows by comparison, but of course all of the quartet's explosiveness came from the songs off its first two albums.

"It was just so powerful, unlike anything any of us had experienced at that point," said Lindsey.

What concerts did we miss on this list? Leave a comment to let us know.

METAL MANIA 2017

Alice Cooper: June 8 at Grand Casino Hinckley ($35-$75), June 9 at Vetter Stone Amphitheater, Mankato ($39-$85).

Tool: June 9 at Xcel Energy Center, St. Paul ($75-$95).

Iron Maiden: June 16 at Xcel Center ($39-$97).

Kiss: July 14, Grand Casino Hinckley ($65-$135).

Guns N' Roses: July 30, U.S. Bank Stadium, Mpls. ($35-$250).