The long wait for Queensland motorists is over, with Brisbane's CLEM7 tunnel set to open on Monday night.

The 6.8-kilometre tollway, the longest road tunnel in Australia, runs under the Brisbane River and connects the suburbs of Woolloongabba on the south side and Bowen Hills in the north.

Lord Mayor Campbell Newman says the tunnel will be free for the first three weeks until the $4.28 toll for cars comes into effect.

"I can now reveal that on Monday night the tunnel will be open," he said.

"So about midnight she will be fully operational, allowing people to save 24 sets of traffic lights in a journey from the Royal Brisbane Hospital to the Princess Alexandra Hospital.

"It is terrific to see this infrastructure finally delivered."

The speed limit will be 80 kilometres per hour unless signed otherwise.

The tunnel is named in honour of Brisbane's longest-serving lord mayor, Clem Jones.