BETHLEHEM, Pa. — Blues Traveler, Gin Blossoms, and the Spin Doctors have been spending their summer winding their way across the country.

On Tuesday, the tour will stop at SteelStacks in Bethlehem.

The bands’ history runs deeper than just a few months on the road together. You can trace their lineage all the way back to the mid-1980s in Princeton, New Jersey, where Spin Doctors singer Chris Barron and Blues Traveler front-man John Popper were high school buddies.

“If the lead wasn’t the repertoire we have with Blues Traveler, me going back to high school with those guys, us going back to New York City with them, the very inception of both bands, the story would be how much history we have with the Gin Blossoms,” Barron tells 69 News.

“Those guys opened for us in the very beginning, and we did some more gigs with those guys opening for us in like the summer of ‘93, kind of at the height of our whole crazy whirlwind thing,” Barron adds.

Blues Traveler guitarist Chan Kinchla says there was even a brief period where Barron was also in the band before Popper introduced him to Spin Doctors guitarist Eric Schenkman.

“(Chris) came to New York and was in Blues Traveler for like a month before we realized we can’t have two lead singers. One’s bad enough,” Kinchla jokes.

Spin Doctors were the first of the three bands to achieve mainstream success. Their 1991 debut album ‘Pocket Full of Kryptonite’ turned them into MTV and radio mainstays, thanks to the hit singles ‘Two Princes’ and ‘Little Miss Can’t Be Wrong.’ The leadoff track, ‘Jimmy Olsen’s Blues,’ also became a fan-favorite.

Gin Blossoms followed suit in 1992. Anchored by the hits ‘Hey Jealousy,’ ‘Found Out About You’ and ‘Allison Road,’ the band’s major label debut, ‘New Miserable Experience,’ has since achieved quadruple-platinum status.

Two years later, Blues Traveler finally broke through with their fourth studio album – fittingly titled ‘Four.’ Kinchla credits A&M Records and college radio for helping the album gain momentum.

“We knew it was good. But we thought our other records were good. And we’d gotten a little better in the studio. Every record we were trying to get some stuff on the radio and maybe break through a little bit,” Kinchla says.

“It slowly built, and we got more and more relationships with radio and with our record company, so it was very much a joint effort to kind of break us,” he added.

‘Four’ spawned the hits ‘Run-Around’ and ‘Hook.’ Kinchla says the latter wasn’t originally meant to be on the album — even though the band had been playing the song live. He says they decided to record it after the label told the band what they were hearing “wasn’t Blues Traveler enough.” Kinchla says A&M wanted more “deeper, quirky cuts.”

“We thought (‘Hook’) was a little novelty because it’s making fun of writing a single, or something. I don’t really know what was going through our heads,” Kinchla jokes.

“At this point that’s become even more well-known than ‘Run-Around’ in some ways,” he said.

Next year, Blues Traveler will be celebrating its 40th anniversary, a milestone Kinchla is still trying to wrap his head around.

“We are way more chill than we were. I mean, the ‘90s and aughts, it was just a messy, riotous party, the whole way,” Kinchla says.

“It makes us more consistently good, playing-wise. We have huge catalogs now, which is pretty fun. But honestly, when I get up on stage and start playing, it’s like it’s its own world, and I really feel like I’m 20 again,” he said.

Barron says he now takes a “love-forward” approach to life. He does not miss the loneliness that came with stardom and the rigors of touring.

“It was a lot of pressure on the relationship with the people that you were out with, and it was frustrating,” Barron says.

“So sometimes you’d be inclined to maybe take a little bit of that out on the people around you, and with good reason, you know what I mean? You’d just be frustrated and lonely,” he added.

But that loneliness has helped Barron appreciate the bond and camaraderie he’s developed with his bandmates.

“There’s a gratitude to have known some people for a really long time who do the same weird job; it’s like being an astronaut or something like that, except it doesn’t have nearly as much redeeming social and scientific value,” Barron says.

The Spin Doctors are also celebrating their own milestone. This month marks the 35th anniversary of the release of ‘Pocket Full of Kryptonite.’ Barron says he’s learned to appreciate the defining nature of the album’s success.

“For better or for worse, maybe I’ll make something better than ‘Pocket Full of Kryptonite,’ maybe I already have made a bunch of stuff that’s better than ‘Pocket Full of Kryptonite,’ I don’t know,” Barron says.

“Maybe someday I’ll do something that’s more famous than that, but for now, it’s very likely that is the thing that I’ll be known for,” he added.

And no, he’s not sick of playing the hits.

“People ask me, do you get tired of playing ‘Two Princes’ and ‘Little Miss Can’t Be Wrong’ and ‘Jimmy Olsen’s Blues’? And I’m like, let me rephrase that question. Do I get tired of playing a song that I wrote and watching a room full of people go nuts? And the answer is no, I don’t. I don’t get tired of that,” Barron says.

“I love those songs, I’m grateful to those songs, and I’m grateful to the guys for being there through this whole thing and putting the grease on those songs that made them hits,” he added.

Kinchla says the individuality of the music and the organic way bands hit it big set the ‘90s apart from other decades.

“All these bands were very different, and grunge was one side of it, so there’s a lot of really interesting homegrown band music at that time,” Kinchla says.

“There weren’t a lot of singer-songwriters or individual people or sad girls or power pop. It was just a lot of quirky bands coming up out of the bowels of these different cities, so that’s kind of what the era was, and it was pretty cool,” he adds.

After years of intersecting and intertwining careers, Kinchala says the camaraderie between the three bands has not waned. Last year, Blues Traveler and Gin Blossoms performed a medley of ‘Run-Around’ and ‘Hey Jealousy’ on ‘Jimmy Kimmel Live!’

“All three bands are alive and kicking and just playing great,” Kinchla says.

“The vibe’s good, and that translates to the show. There’s a lot of sitting-in going on, and we have fun just enjoying the summer and rockin’ out,” he shares.

Blues Traveler, Gin Blossoms and Spin Doctors perform Tuesday at SteelStacks in Bethlehem. Gates open at 5:30 p.m. Show time is 6:30 p.m.