The atmosphere on the concourses in Cardiff after the first Oasis gig of their long-awaited reunion tour was one of speechlessness that the once-estranged Gallagher brothers had pulled it off.

Leigh, from Cardiff, could hardly find the words to describe the two and a half hours he had just witnessed. “They were quiet at the beginning, then the crescendos went wild, then they were non-stop wild,” he said. “It went supernova – crazy. I couldn’t believe it. I don’t know what to say – I was 18 again.”

He had attended with his 22-year-old daughter and her boyfriend. “They didn’t know Oasis and came for the experience. It was the best night. They’ve been to concerts before but never like this – it was a new level.” During Stand By Me, the trio had a cuddle – or a cwtch, in Welsh – “two generations together. I’ve convinced her throughout the years that they’re the best band, and she was ecstatic to get to this point on her journey.”

The show had been “100%” worth the money, he said. “I could’ve gone away with the family for two weeks, all-inclusive, in the sun, but I wouldn’t swap it.”

Jack from Stockport, described the concert as “biblical: the presence, everything,” he said. “There was no silence during the set at all, everyone was singing as one.”

It wasn’t until the very end of the set that Liam and Noel Gallagher acknowledged each other: Liam walked towards his brother, clapped him on the back twice, and then immediately escaped in a Range Rover waiting on the side of stage to drive him to sanctuary; presumably a similar car awaited Noel on the other side. “The one time they interacted, they looked like actual brothers,” said Jack. “Though Liam didn’t look as if he was giving Noel a lift home.”

His partner, Beth, appeared out of the women’s loos, heavily pregnant with the pair’s twins – their first in utero gig. Beth was born a month after the band’s famous performance at Knebworth in August 1996. Had they considered Noel and Liam as potential names? “They’re girl twins,” she said. “But we did think about Lyla” – a song from 2005’s Don’t Believe the Truth – “as a name for a little bit.”

Couple Jarvis and Valentina had travelled from north London for the show. “It was absolutely incredible,” he said. “Liam’s voice hasn’t sounded that good since the mid-90s. At the end of the 00s his voice was shot. That’s incredible.”

The pair knew what they were talking about: Valentina said they saw them about 40 times during their initial incarnation. She had moved from Italy to the UK in the year 2000 because of her love for the band. “We used to follow them everywhere,” she said of herself and her teenage girl friends. Once in Florence, she said, they snuck into the band’s hotel “and spent the afternoon drinking with them.”

She clarified: “There was no malice. We were good Italian girls. But Liam was drinking from 2pm until 7pm, and by the end I was seeing double. We talked about the Beatles. We would follow them everywhere and if we didn’t have a ticket, they would say, ‘Girls, do you have a ticket?’ and get us in.”

Tonight’s show, she said, brought back “so many memories of happy, better times, lots of us cried. They’re a working-class band and they attract that audience: no band has touched a generation like that.”

“If I’d dreamed it,” said Jarvis, “they couldn’t have been better.”