Thousands of AFL fans have poured into Fremantle to cheer on the port city's beloved Dockers as they watch the grand final in pubs and on big screens on the cappuccino strip.

The main drag of South Terrace, which has been closed to traffic, filled rapidly with crowds in the lead up to game time.

Mayor Brad Pettitt said he was too young to have experienced the America's Cup celebrations in 1983, but almost 30 years to the day, was told the partying in the port city was exceeding that historic win.

"It's an absolutely amazing day - it's a sea of purple all the way down the cappuccino strip," Mr Pettitt told AAP.

"There's an incredible buzz. It's something I've never experienced."

Mr Pettitt, who is tipping a 17-point win for the Dockers, said he'd spend the day in the heart of town soaking up the atmosphere.

At the Sail and Anchor pub, which opened at 8am (WST), wait staff said they were getting "flogged" by the rush of patrons.

The heritage-listed landmark was immediately serving plenty of its specially brewed purple Freo Victory Lager along with a BBQ breakfast.

The pub could run out of beer by the end of the long Queen's Birthday weekend, the manager said. Last weekend, it almost ran dry as Dockers fans celebrated the team's convincing preliminary final win.

"The queue started at 6am and we're currently just under our 520 person capacity," he said around 10.30am.

"At this rate, by Monday, we may well be out of beer but we're hoping people will have sore heads by then," he laughed.

Sales of the Freo Victory Lager were "going through the roof", he said, and the atmosphere was joyous.

At the nearby Norfolk Hotel, a queue of about 150 footy fans formed long before the pub could open its doors at 10am.

A spokesman for the local council said intensive planning for the big day was paying off.

"Everything is going to plan," he said.

At the Inglewood Hotel, which is home to Hawks fans, long queues formed well before the pub's 9am opening.

Fortunately, a brief power outage in inner-city suburbs including Bedford and Baywater didn't affect the hotel.

A spokesman said about 500 Hawthorn supporters had crammed into the pub just before midday.

"The mood here is pretty jovial," he said.