Travellers planning to cross the Queensland border from NSW are being warned of queues up to 20 kilometres long when the boundary reopens after being closed for more than three months.
From midday on Friday, Queensland's borders will open for the first time since closing on March 25 to stymie the spread of COVID-19.
Travellers will require identification and a border declaration stating they have not visited Victoria over the previous 14 days to enter Queensland.
Victorians will be turned away from the border if they seek to enter Queensland.
NSW Police is urging motorists to be prepared to provide all relevant documentation and identification at checkpoints to help reduce delays.
Thousands of motorists are expected to travel into and through NSW's Far North Coast region and NSW Police Superintendent Dave Roptell urged drivers to be patient.
"If you are choosing to cross the border in the next 72 hours, please be aware we anticipate there will be extensive delays at the major checkpoints - these delays could be more than a couple of hours, with queues potentially up to 20km long," Supt Roptell said in a statement on Thursday.
"We are working with our counterparts over the border to ensure as smooth a transition to the new border pass system as possible, but we understand this will take time to work through."
Those who do not need to cross the border on Friday are being asked to delay their travel to allow the large influx of traffic to flow through checkpoints, Supt Roptell said.
"If you do decide to cross the border, make sure you are well prepared - have some snacks and water in the car, stop off at a rest stop or coastal town for a pit stop and bathroom break before piling into the car," he said.
Those planning to visit popular tourist destinations such as Byron Bay, Bangalow, Ballina and Suffolk Park are also reminded to follow social distancing guidelines and public health orders.
"We are not out of the danger zone yet," Supt Roptell said.
"With thousands of NSW residents now able to travel across the state, we are seeing a massive influx of visitors to our popular coastal spots."
Interstate travellers who develop COVID-19 symptoms while in Queensland will be forced to get tested or face a $4004 fine.
Freight drivers are exempt from the new rules.