At this year's double dissolution election, the tables were turned and Old Parliament House was the place where electors performed their civic duty.

Several thousand Canberrans and interstate voters crammed into the building, now home to the Museum of Australian Democracy, to cast their ballots inside the old members' dining room.

This election was the second time that Old Parliament House had been a polling centre. There was a far greater level of interest in casting a ballot in Canberra's original halls of democracy this time compared with the 2013 poll.

Some voters waited for up to an hour in the lines snaking around the Senate and House of Representatives chambers.

To help pass the time, the museum employed two actors imitating 1920s journalists, who asked punters whether they preferred Jim Scullin (prime minister from 1929 to 1932) or Stanley Bruce (prime minister from 1923 to 1929) as the nation's leader.

Voters were rewarded with cartoon badges and a special pencil after casting their ballot to mark the occasion, while children had the chance to cast their own ballots in the Play Up centre.

For those who had built up an appetite in the queue, a quintessential election sausage sizzle was available in the car park outside.

Museum exhibition, engagement and heritage head Edwina Jans said she was pleased so many people, particularly from interstate, had been drawn to the iconic building.

"It's a symbol of national unity and an expression of our history; the decisions made here are still resonating today," she said.

"That's also what we're doing today, we're making really important decisions about how we as a country want to live."

Elsewhere across the capital, voters took to polling booths under blue but frosty skies.

Mid-morning to late afternoon was reportedly the peak period for voting, with numbers dwindling as the sun set.

Up to 43,000 ACT residents, similar to numbers at the 2013 election, opted to avoid the crowds and forgo a sausage sandwich by visiting pre-polling centres before Thursday.