Harbour Bridge climber known to police

Security on the Sydney Harbour Bridge is being reviewed after a mentally ill man brought traffic to a standstill by climbing onto the iconic structure before the morning rush hour.

The 43-year-old man sparked a major police operation lasting five hours, with NSW Police later saying he climbed up the bridge due to a "family issue" and he suffered "significant mental health issues".

The man scaled the bridge about 4.30am on Wednesday and surrendered to authorities just after 9.30am. He was handcuffed by police rescue officers and brought down to the ground.

Superintendent Michael Fitzgerald says the man - who rode a bike to the bridge - was known to police and would face "significant charges" after being treated in hospital.

"He has got significant mental health issues, which hopefully the expertise of St Vincent's Hospital will address," Supt Fitzgerald told reporters in Sydney.

"We were concerned he was going to harm himself but also we were concerned about what harm could have been occasioned to innocent members of the public driving underneath him."

NSW Roads Minister Melinda Pavey labelled the bridge climb a "premeditated event" and is considering tripling the current $3000 penalty for trespassing on the structure.

The minister suggested the $10,000 fine for illegally climbing San Francisco's famous Golden Gate bridge was a "good starting point".

"You can't stop people doing stupid things but you can have a range of measures in place to limit the amount of times it happens," Ms Pavey told reporters.

"Sending a big fine, a big message, will stop this thing happening in the future."

During Wednesday's incident, two special operations team paramedics also ascended the bridge in harnesses to assist police in the event that the 43-year-old required sedation.

Traffic was backed up 20 kilometres from the bridge during peak hour with authorities closing several northbound lanes as negotiators talked with the man.

Supt Fitzgerald apologised to motorists but insisted "safety was paramount".

He said authorities would work with the Roads and Maritime Service to make the bridge more secure.

NSW opposition spokesman Guy Zangari said the government needed to better co-ordinate all agencies that manage aspects of the bridge.

"There were 10 security officers and CCTV footage and yet an individual has brought the city to a complete standstill," Mr Zangari said on Wednesday.

Climbing the Harbour Bridge is illegal unless authorised, for example as part of an official Bridge Climb Sydney tour.

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