"We perform sacred dances and ceremonies for you to enjoy and see our ancient traditions," Uncle Max told an attentive crowd gathered around the smoking fire pit at the WugolOra ceremony at Barangaroo on Thursday morning.

Nearly 2000 people attended the event, organised by the NSW Department of Premier and Cabinet, which commenced with a smoking ceremony led by the Koomurri Aboriginal Dance Troupe.

"We were paying respects to Mother Earth and asking permission to be here," said Clarence Slockee, who helped make the bark nawi (canoe) carried by the troupe.

"For us, it's about reconnecting ancient songlines."

Just after 8am the Australian and Aboriginal flags were raised in concert on the Sydney Harbour Bridge.

A 150-strong choir headed by Jacinta Tobin and Nardi Simpson gathered around the sandpit to sing Budjari Gunyalungalung Baraya-la (Let's Sing the Good Dreaming) to a swelling crowd.

As the choir finished, Yvonne Weldon, chairwoman of the Metropolitan Local Aboriginal Land Council, addressed the audience.

"Aboriginal people are the most diverse and sustainable people in this country," she said.

"Our voices must be heard. But don't just hear us, listen to us.

"This always was and always will be Aboriginal land. We have survived," she said to cheers from the audience.

Barangaroo is a significant Aboriginal cultural heritage site, named after a Cammeraygal woman who is remembered as a significant leader of her people at the time of European colonisation.