Thousands celebrate Australia Day in true blue style

People around the country have marked Australia day in true blue style, with thousands packing beaches and parks in boardies and bikinis.

In Sydney hundreds of thousands are expected flock to the Harbour throughout the day for festivities, including the annual Sydney Harbour Ferrython and the tall ships display.

Hundreds of thousands of people are expected to flock to Sydney Harbour. Source: 7News

Tall ships display at the Harbour. Source: 7News

In Watsons Bay four-legged friends joined in the annual Australia Day stand up paddleboard event,'Every Man And His Dog'.

There has also been hot air ballooning over Parramatta Park.

Hot air ballooning over Parramatta Park. Source: @NatashaSquarey/ Twitter

Thousands spent the day in the sun in the sunshine state with Queenslanders enjoying some beach cricket and barbecues at Burleigh Heads.

Thousands flocked to the beach to mark Australia Day. Source: @KrystalENews/ Twitter

Also on the Gold Coast one family captured their pet Cockatoo, Wally, getting into the spirit and raising the Australian Flag.

A family has filmed their Cockatoo raising the Australian Flag. Source: Mark Culleton

At Brisbane's Story Bridge Hotel cockroach racing was one of the main attractions, attracting a bumper crowd.

In Victoria, mates put snags on the barbie by the Yarra, while in Perth temperatures have soared to 40 degrees, becoming the city's hottest Australia Day in five years.

Snags on the barbie by the Yarra: @pauldowsley7/ Twitter

AAP reports, more than 16,000 migrants from 150 countries celebrated becoming dinky-di Aussies at 400 citizenship ceremonies across the country as huge crowds gathered at some truly distinctive Australia Day events.

But amid the colourful celebrations were large protests in capital cities and plenty of debate about changing the date of Australia Day in recognition of the pain felt by many indigenous people over the annual marking of the First Fleet's arrival from England 229 years ago.

Thousands turned out at "Invasion Day" rallies in central Sydney and Melbourne chanting "always was, always will be Aboriginal land", while hundreds more took to the streets of Brisbane and staged a sit-in outside Parliament House in Canberra.

The Sydney protest turned violent momentarily as police clashed with demonstrators after a flag was apparently set alight.