The most significant road closures in Canberra's city centres in more than half a century will begin on December 2, as the southern end of London Circuit is closed to traffic.
The two clover-leaf exits to the west of Commonwealth Avenue will also be closed permanently, as work continues on the raising London Circuit project.
The southern end of London Circuit between Edinburgh Avenue and Constitution Avenue will close from Friday next week, part of the government's long-term plans to extend light rail to the south.
Transport Minister Chris Steel said Canberrans travelling to the city should "rethink their routine", particularly if they were coming towards the city centre from the capital's south side.
"Traffic mitigation measures will ensure Canberrans and visitors can still access the city, visit their favourite shops and cafés or receive the local services they need. We just ask everyone to plan their trip and be patient while changes take place," Mr Steel said in a statement.
"Project planning has been more than a decade in the making. It's what Canberrans voted for at multiple elections, and now we're getting on with the job of delivering on that promise."
New traffic lights and a bus lane on Vernon Circle will manage the additional traffic during the construction period.
The government believes the biggest impact on commuting times as a result of the work will be in the morning peak.
The works will mean the intersection reverts to its original layout, before the network of overpasses and clover-leaf turns were installed in the late 1960s, in works that shut the southern end of London Circuit at the time for more than a year.
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