The Sydney Opera House Concert Hall filled with the sound of regional NSW on Saturday as more than 400 young performers - from primary to high school age - took to the stage to celebrate Moorambilla Voices' 21st anniversary in its first full-scale Concert Hall gala.

The performance featured new compositions, dance, Taiko drumming and visual storytelling shaped by the landscapes, languages and cultures of regional NSW, with performers travelling from towns including Griffith, Bourke, Wellington and Tamworth.

Founder and artistic director Michelle Leonard OAM grew up in Coonamble, western NSW, where she says choirs and a town band were once simply part of everyday life.

Moorambilla Voices became her answer. She founded Moorambilla Voices in 2006 after recognising the untapped potential of young people in regional and remote communities who did not have access to the same quality music education opportunities as their metropolitan counterparts.

"I wanted everyone to have an opportunity to learn, to sing, to read music," Leonard said.

"That's what this has always been about, giving regional young people the opportunity to step onto the Concert Hall stage - some of them from towns most Sydneysiders have never heard of.

"The October Gala celebrates two decades of our young people working alongside professional artists to co-create ambitious new Australian works that speak with purpose and joy about our shared connection to Country.

"To bring more than 400 young people together on the Concert Hall stage of the Sydney Opera House is an extraordinary milestone and a powerful celebration of the confidence, artistry and sense of belonging that is fostered when young people see their communities and stories valued on a world stage."

Moorambilla was delighted to welcome associate artists from its collaborating youth ensemble, incorporating musicians from the Australian Youth Orchestra.

"Moorambilla combines exceptional music-making with deep community connection," said Australian Youth Orchestra CEO Kimbali Harding.

"Their young choristers are outstanding, and their commitment to creating and commissioning new Australian work is genuinely inspiring.

"Working alongside them gives our musicians a rare opportunity to learn from artists and communities whose creativity, generosity and cultural leadership are helping to shape the future of Australian music."

The gala brings current participants together with Moorambilla alumni, including Justin Welsh, who first found his voice as a young Moorambilla participant and now returns as an Indigenous language consultant for the next generation.

"Returning to Moorambilla to teach feels like completing a circle," Welsh said.

"This program changed what I believed was possible for my own life, and now I can help young people understand that their language and culture belong on the world's biggest stages.

"Every word they learn and carry home keeps the language moving forward, and hearing it ring through the Opera House will show those children that where they come from matters."

Brenna Hobson, director of Programming at Sydney Opera House, expressed how proud Sydney Opera House was to be involved in the celebration.

"We're proud to celebrate this milestone with Moorambilla Voices as we honour the many stories, voices and talents of the bush and regional NSW," she said.

"We're looking forward to welcoming Moorambilla's community of performers, families and artists to Sydney.

"Bringing more than 400 young people to the Concert Hall stage is a powerful reminder of what's possible when young people are empowered to dream. We hope this moment inspires the next generation of artists and leaders and we invite Sydney audiences to discover the extraordinary creativity flourishing across regional Australia."

The landmark event arrived at a critical time for arts education, highlighting how access to the arts has become harder over recent years.

A study by the Australian Council for Educational Research found only 32% of NSW primary teachers regularly taught music, while just 17% said their school used a specialist classroom music teacher.

This experience is heightened further for regional communities, as Creative Australia states that those living in remote Australia were twice as likely to experience difficulty accessing arts events, despite being more likely to attend for their wellbeing.

Since Leonard founded Moorambilla Voices in 2006, the organisation has delivered skills-development workshops, cultural immersions, residency camps and performances to more than 58,000 young people across 140 schools in regional and remote NSW - work documented in the Netflix documentary Wide Open Sky.

More than a 21st-anniversary celebration, the Gala was an invitation for metropolitan audiences to experience the creative excellence growing beyond Australia's cities, and a reminder that talent is everywhere, regardless of postcode or circumstance.

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