Queensland's border with NSW has officially closed with road access blocked to everyone except essential workers and locals living along the interstate boundary.
Chief Health Officer Jeannette Young declared NSW and the ACT coronavirus hotspots on Saturday as the southern border closed for the second time since the coronavirus crisis began.
"These new, tough border restrictions are all about keeping Queensland and Queenslanders safe," Heath Minister Steven Miles said.
"They are all about keeping the virus out of Queensland."
Residents were urged to get home ahead of the 1am closure with thousands caught in heavy traffic at crossing points in the Tweed region on Friday.
Queenslanders returning from hotspots including Victoria must now arrive by air and enter a 14-day hotel quarantine at their own expense.
Non-Queenslanders from hotspots will need an exemption before they are allowed to enter the Sunshine State and will also face quarantine.
People from non-hotspot locations can fly in, or enter the state through the Northern Territory border.
Border locals from 41 postcodes along the boundary will need a pass to cross in and out of Queensland, but must not travel beyond their local area.
The decision to close the NSW border and ban ACT residents came on Wednesday, as Victoria recorded its deadliest day of the pandemic so far.
"Victoria hasn't improved as we hoped and I won't wait for NSW to get any worse," Premier Annastacia Palaszczuk said at the time.
"I will not risk the safety of Queenslanders and I will not risk our economy."
The closure comes as authorities urged people to observe coronavirus health restrictions over the weekend.
"Maintain 1.5 metre distance at all times and wash your hands. All of those things are critical," Dr Young said.
The government will review the border closure at the end of August.
What does this mean for NSW residents?
NSW residents are essentially confined within their own state again after Queensland's new border restrictions came into effect early on Saturday.
Travel to Victoria is discouraged by the NSW government, leaving only the Northern Territory, which has barred Sydneysiders but is accepting travellers from some NSW regions.
It comes as NSW ramps up its own travel restrictions.
From Friday, NSW residents returning from coronavirus-hit Victoria must now complete two weeks of hotel quarantine.
Entry to NSW from Victoria is now restricted to flights landing at Sydney Airport, except for border community residents with permits.
Those returning through the airport will be sent into 14 days of hotel quarantine at their own expense, alongside those returning from overseas.
NSW Police Commissioner Mick Fuller said hotel quarantine had been one of the state's most effective tools in preventing the spread of COVID-19.
"Make no mistake - mandatory hotel quarantine has undoubtedly saved many lives, particularly among our vulnerable community members, and will continue to do so as we navigate this public health threat," he said in a statement on Friday.
It comes as NSW recorded 11 new COVID-19 cases in the 24 hours to 8pm on Thursday, including one who attended The Apollo restaurant in Potts Point and eight who are close contacts of known cases.
One case, a female in her 60s from Sydney's southwest, is still under investigation, while one new case acquired in Victoria is in self-isolation.
People in Australia must stay at least 1.5 metres away from others. Check your state’s restrictions on gathering limits.
If you are experiencing cold or flu symptoms, stay home and arrange a test by calling your doctor or contact the Coronavirus Health Information Hotline on 1800 020 080.