This spring, the operators of Vetter Stone Amphitheater in Mankato were on pins and needles, worrying that they would have to cancel another season of concerts. Then it was like a switch suddenly flipped.

"Our phones started ringing off the hook," said the amphitheater's co-director, Eric Jones.

He was referring to the days after Gov. Tim Walz announced the rollback of Minnesota's COVID-19 restrictions on May 6. More concerts have been added to Vetter Stone's calendar since then, and ticket sales have spiked.

The Twin Cities remains by far the largest concert market in the United States without a sizable permanent amphitheater. But outdoor venues around Minnesota are suddenly feeling confident this will be the summer they draw city-dwelling music lovers to their seats and grassy general-admission areas.

Crew members at the new $11.5 million Ledge Amphitheater near St. Cloud — which had to postpone its opening last summer — were just two weeks away from canceling all their concerts for 2021. Instead, they've added a couple of events since May and are hoping for one or two more.

"It's a little late in the game to be planning for this summer, but we're thrilled to have the option," said Ledge promoter Chris Fritz.

Treasure Island Casino in Red Wing opened Minnesota's largest and most legit amphitheater in 2018 with the goal of drawing fans from the metro area.

The 16,000-person venue — with about two-thirds of its seating being permanent seats on tiered concrete — is comparable to industry-standard amphitheaters such as Chicago's Tinley Park (aka Hollywood Casino Amphitheater) or Kansas City's Starlight Theatre, which are loaded up with major tours every summer.

"We think our amphitheater is becoming known in the touring industry as a good destination venue," said Treasure Island publicist Aaron Seehusen.

Case in point: Country megastar Luke Bryan, who last performed in Minnesota at Target Field, added a Sept. 3 date there on relatively short notice once vaccine rates in the state started spiking in April.

Mystic Lake Casino also landed a couple of big gigs after it became clear that COVID restrictions would be loosened: John Fogerty of Creedence Clearwater Revival fame (July 4) and the reunited Jonas Brothers (Sept. 11).

Mystic Lake was already betting on concerts returning to full capacity with two big gigs booked in June, including Friday's return of Darius "Hootie" Rucker. Country music vets Alabama played to 8,000 happy fans there two weekends ago — the first concert of that size in Minnesota since before the pandemic.

Tim Nelson, 47, of Stillwater, wasn't nervous about being in the big crowd: "I'm vaccinated. I feel good. It's outdoors. I brought a mask just in case."

Masks are no longer required at large outdoor gatherings in Minnesota, but some COVID-related safety measures still will be in place at these amphitheaters.

Treasure Island's first outdoor show, with Foreigner on July 2, will feature socially distanced seating (easy to do, since the "Hot Blooded" hitmakers are down to only one original member and not exactly a hot ticket nowadays). Vetter Stone's crew in Mankato is encouraging fans to "sort of naturally spread out" in their general-admission areas and wear masks at concession stands, Jones said.

At Bayfront Festival Park in Duluth, concert organizers are trumpeting the fact that the scenic harbor-side amphitheater has 10 acres of space with room for 20,000 people.

"People can still push together down in front of the stage if they're vaccinated or aren't worried," said Chris Mackey, director of the Bayfront Blues Festival, returning Aug. 13-15. "But there's also plenty of room for anyone who wants to be more cautious and sit off by themselves on the grass somewhere."

Within the Twin Cities, various outdoor spaces are being used by promoters as substitutes for a real metro area amphitheater, including Canterbury Park in Shakopee (where Twin Cities Summer Jam returns July 22-24) and Surly Brewing Festival Field, next to the mega-brewery in Minneapolis (Patti Smith on Aug. 7 and Ween on Aug. 21).

Surly's concerts are booked by First Avenue, which has been working with Minneapolis officials to build an under-10,000-capacity amphitheater north of downtown, in the former Upper Harbor Terminal along the Mississippi River. Planning got held up by the pandemic along with everything else. Look for a groundbreaking maybe next year, with completion two or three years after that.

Until then, amphitheaters around the state are happy to have Twin Citians come visit. In fact, they're counting on it.

"We've always pitched our venue as being worth the drive," said Jones at Vetter Stone. "I think that's especially true this year with everyone eager to get outdoors and have fun."

The Ledge Amphitheater

Location: In former granite quarries at 1700 Parkway Drive in Waite Park, just east of St. Cloud, 73 miles northwest of Minneapolis.

Setup: The new, partly state-funded venue holds around 6,000 people, with about 4,500 permanent seats plus general admission in the back.

Shows: Rock Gods tribute band (July 16); Great Theatre's "Cinderella" (not the '80s hair band, July 22-24); Dropkick Murphys and Rancid (Aug 10); Beach Boys (Aug. 11); 311 (Sept. 12).

Vetter Stone Amphitheater

Location: A few blocks from Mankato's historic downtown near the Minnesota River, 310 W. Rock St., 80 miles southwest of Minneapolis.

Setup: About 3,300 reserved seats along large tiers of limestone, with an open grass field and general-admission areas that hold 4,500 more.

Shows: Aaron Lewis (Sat.), the Mavericks (July 22), Old Crow Medicine Show (July 29), Beach Boys (Aug. 12).

Treasure Island Casino Amphitheater

Location: Across the large parking lots outside the resort and casino complex in Red Wing, 5734 Sturgeon Lake Road, 45 miles southeast of Minneapolis.

Setup: About 9,400 permanent seats and a grassy general-admission area with real restroom facilities.

Shows: Foreigner (July 2), Island Block Party with Elton John tribute (July 3), Gabriel Iglesias (July 31), Luke Bryan (Sept. 3), Wilco and Trampled by Turtles (Sept. 18).

Mystic Lake Casino Amphitheater

Location: Outside the casino and hotel in Prior Lake, 2400 Mystic Lake Blvd., 25 miles southwest of Minneapolis.

Setup: Without a permanent facility such as Treasure Island's, Mystic Lake's concerts are laid out on a large, slightly inclined grass field with folding chairs, portable toilets and a grassy general-admission area.

Shows: Darius Rucker (Fri.), John Fogerty (July 4), Jonas Brothers (Sept. 11).

Bayfront Festival Park

Location: In the shadow of the iconic Aerial Lift Bridge and Great Lakes Aquarium alongside Lake Superior in Duluth, 350 Harbor Drive.

Setup: The impressive seven-story, steel-canopy stage overlooks a large flat concrete slab for seating surrounded by grass and permanent park facilities.

Shows: Bayfront Country Jam with Aaron Tippin (July 2); Hairball (July 3); Bayfront Reggae & World Music Fest with Anthony B and Third World (July 17); City on the Hill Christian music fest (Aug. 6-7); Bayfront Blues Fest with Fabulous Thunderbirds, Tab Benoit, CJ Chenier (Aug. 13-15).

And don't forget ...

Canterbury Park: Shakopee's horse track will host the TC Summer Jam with the Zac Brown Band, Carrie Underwood and Lynyrd Skynyrd (July 22-24). Then promoters Sue McLean & Associates will present shows there in lieu of their usual Music in the Zoo series, including Old Crow Medicine Show (Aug. 2), En Vogue (Aug. 6), Steve Earle (Aug. 7), Robert Cray (Aug. 16), Daughtry (Aug. 21) and Blackberry Smoke (Sept. 3).

Hilde Amphitheater: Two more shows from Sue McLean's team at the grassy Plymouth venue in one weekend, with the BoDeans (July 17) and Okee Dokee Brothers (July 18).

Big Top Chautauqua: Beloved by Minnesotans even though it's across the border in Bayfield, Wis., the scenic hilltop venue overlooking Lake Superior has a new permanent setup and a still-solidifying 2021 lineup that includes Tanya Tucker (July 17), the Mavericks (July 18), Steve Earle (Aug. 6) and Wynonna (Aug. 8).

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