But this year's Australia Day festivities are more likely to elicit raised eyebrows, skipped heartbeats, and perhaps even the odd wolf whistle.

The gallery will combine Triple J's annual Hottest 100 music countdown with another national pastime - a good old perve.

Its Hottest 100 Party will also feature a countdown of the most swoon-worthy Australians whose portraits are in the gallery's collection.

Program co-ordinator Katrina Osborne said the concept came from a desire to mark the national day in a relaxed way that also celebrated portraiture.

"The Hottest 100 has become a pretty iconic way to celebrate Australia Day so we thought why not mirror that with showing some of the hottest people in the collection," she said.

The music countdown will blare as revellers knock back a few drinks, fire up the barbecue and take part in some vintage-style backyard games.

The celebrations will be accompanied by a slide show of roughly 100 portraits in the gallery's collection which guests can vote on before the list is whittled down to a top 10.

"We've got everyone from Deborah Mailman to Marcia Hines and Lionel Rose to Cathy Freeman.

"We've got Dame Edna Everage, if that floats your boat, Megan Gale, Heath Ledger."

"You can look at the portraits from a really artistic perspective or through a historical lens, but on Australia Day why not strip back the seriousness and look at the collection through different eyes."

Elsewhere in the capital, police are gearing up for the big crowds expected in the city for Sunday evening's Australia Day Live concert in front of Parliament House and Monday's festivities in Commonwealth Park.

Australia Day operations commander Sergeant Jim Edwards said police would focus on underage drinkers throughout the weekend.

"Young people drinking is a risk to them because they're unsafe, they can't look after themselves, they're not used to drinking large amounts of alcohol and they're susceptible to other violent events that might take place."

"Throughout the weekend we want everyone to behave themselves. Have a good time - it's a wonderful weekend to celebrate - but we want everyone to look after themselves and look after each other."

Sergeant Edwards said last year's crowds were "fantastic" and although one drunk teen was taken into custody, no one was arrested.

A police spokeswoman would not be drawn on whether officers were concerned about racial tensions flaring up during celebrations.

"ACT Policing will be at the planned events across the Australia Day weekend and has sufficient operational resources to respond to incidents as required."

Traffic police will have motorists who are drunk, speeding or not wearing a seatbelt in their sights.

Last year, 21 drivers were nabbed for drink driving by the police, who carried out 2330 roadside breath tests.

Double demerits are in place until midnight on Monday.