The federal government has banked $122.5 million from the sale of four properties in Canberra's parliamentary triangle, including $15.5 million for the home of the National Archives of Australia.
Finance Minister Mathias Cormann announced on Thursday the historic East Block, Anzac Park West and East buildings and a development site on Constitution Avenue had been sold to developers.
Senator Cormann said EG Funds Management Pty Ltd had bought the Anzac Park West site for $51 million and the East Block for $15.5 million.
Amalgamated Property Group paid $34.3 million for Anzac Park East and $21.7 million for the Constitution Avenue development site.
"Private investment presents an opportunity to revitalise all these properties and ensure the significant heritage values are retained," he said in a statement.
"All sales agreements include comprehensive protections to preserve the heritage values and significant architectural merit of the properties in perpetuity."
In September, the West Block was sold for $6.25 million, with new owners Geocon planning to turn the historic building into a boutique hotel.
The sales mark the first private land ownership inside the parliamentary triangle which includes Parliament House, the High Court and the National Gallery of Australia.
The East Block, home to Canberra's first general post office, will be leased to the National Archives for at least 10 years.
The announcement came as the National Capital Authority confirmed plans to sell the Lobby Restaurant Building near Old Parliament House, months after Aboriginal Tent Embassy activists were removed from the site by police.
Authority chairman Terry Webber and acting chief executive Andrew Smith fronted a hearing of Parliament's joint standing committee on the National Capital and External Territories, saying the building's new owners could use it as a cafe or restaurant, function or conference venue.
Last month The Canberra Times reported the federal government was finalising plans to sell the disused restaurant before Indigenous land rights activists began a controversial occupation.
Activists forced their way into the restaurant in an attempt to reclaim what they described as Ngunnawal sovereign land
Mr Webber said money raised from the building's sale would be reinvested in the national estate.
"It requires reasonably extensive work done on it. If you were to lease it out to a restaurant provider, I'm think [it would require] $300,000-$400,000 in work," he said.
The building has been left empty after previous commercial tenants left before their lease expired, with it's prolonged vacancy prompting renewed land rights tensions around in the Tent Embassy encampment.
A new permanent authority chief executive is expected to be announced within days, after former boss Malcolm Snow left to join the ACT government.
Mr Smith told Canberra MP Gai Brodtmann the new owners of the West Block faced strict heritage provisions for the redevelopment process.
"There's two heritage overlays. Those contained by the National Capital Plan and our approval regime and there are those contained within the lease, which requires they have a heritage management plan.
He said no assessment had been made to any possible changes to the building's facade.