The public gallery is expected to overflow when the ACT Legislative Assembly debates same-sex marriage legislation next week.
Televisions will be brought in to allow members of the public to watch the historic debate.
MLAs will debate the bill on Tuesday and it could pass as early as that day with the support of the eight Labor MLAs and Greens MLA Shane Rattenbury.
The ACT is expected to become the first Australian jurisdiction to pass same-sex marriage laws after the Tasmanian parliament delayed debate of its marriage equality by two weeks.
Australian Marriage Equality deputy director Ivan Hinton said the ACT was days away from ''making history and embracing a reform that has become an aspiration for all Australians that value fairness and equality''.
''From 10am next Tuesday eyes from around the nation and the world will be watching as Canberra becomes the most inclusive place in Australia for same-sex couples,'' Mr Hinton said.
''We know thousands of same-sex couples from across Australia have indicated their interest in marrying in the ACT and these weddings will begin soon after the bill passes, regardless of any federal government intervention.''
The marriage equality group is calling on the ACT opposition to allow MLAs a conscience vote on the bill. But the Canberra Liberals have backed the Abbott government's plans to challenge the laws in the High Court as soon as they are passed.
Family Voice Australia national research officer Ros Phillips said ACT MLAs on both sides of government should be ''open to looking at the principles involved and realise that marriage, according to our national constitutional experts, is a national institution''.
''It's not something that can be one thing in one place and something different somewhere else,'' Mrs Phillips said.
''You could get married in Canberra and your marriage won't be recognised over the border in Queanbeyan.
''What is the point?''