Thousands of protesters have gathered in Canberra's CBD and are preparing to march to the Aboriginal tent embassy, which marks 50 years of activism.
As Prime Minister Scott Morrison and other dignitaries gathered for an Australia Day citizenship and flag-raising ceremony, Indigenous people dressed in traditional garb conducted a ceremony at Garema Place before a minute's silence was held ahead of the march for "the warriors before us".
Stalls and speech tents have been set up at the tent embassy, situated near Old Parliament House.
Helicopters displaying the Australian flag and a low military flyover contrasted with a seas of shirts displaying the Aboriginal flag and statements of Indigenous sovereignty.
Speaking after the citizenship ceremony, federal Labor Leader Anthony Albanese said it was important to recognise Australia's history went back at least 60,000 years.
"Which is why one of my priorities will be to recognise First Nations people in Australia's constitution," he told reporters.
"We should be very proud that we are home to the oldest continuous civilisation on the planet."
In Melbourne, a statue of Captain James Cook was smeared with red paint.
