Holidaymakers faced huge traffic jams north and south yesterday as they tried to leave Auckland.

The Northern Gateway toll road and the Kopu Bridge entry to Coromandel Peninsula were jammed as thousands deserted the city for a summer break.

And to add to the misery, the petrol motorists were burning as they waited in the queues was costing them an extra 2c a litre after prices crept up again.

Bumper-to-bumper traffic stretched almost the length of the 7.5km toll road between Orewa and Puhoi for three hours from late yesterday morning.

Some hot and frustrated drivers and passengers got out of their cars to stretch their legs and cool off.

Angry motorists vented their frustration on Twitter.

Doug Hanna wrote that he had visitors from Auckland staying with him at Oakura, north of Whangarei: "Took 5 hours 40 to get here today. Took us 3.10 yesterday."

Hamish Rouse was travelling in the opposite direction: "NZ Traffic anywhere out of Auckland is insane. Just came down from up North. Poor northbound travellers."

James Green was missing the sporting event of the day: "Goddamn Auckland traffic. Only trying to get somewhere to watch the [Ashes] cricket."

Police assisted drivers of seven overheated vehicles at the side of the road, said Sergeant Dave Reid of the Waitemata highway patrol.

Ulrik Olsen said it took him 2 hours from 12.15pm to drive the 104km from Auckland to Mangawhai - including about 40 low-speed minutes on the toll road and then stop-start travelling on much of the rest of the journey.

"Warkworth was not pretty either," he said of a jam back from the town's turn-off to Snells Beach and Matakana.

He said the queue on the toll road started only about 200m north of the Orewa turnoff to the free coastal route, which was relatively uncongested.

The giant traffic jam was caused by two lanes of motorway traffic having to merge into one lane before the Johnstone's Hill tunnel, and then merge again with vehicles from the coastal road on the one northbound lane beyond the toll road.

Although the Government has designated a $1.65 billion four-lane highway from Puhoi to Wellsford as one of seven "roads of national significance", the first stage to Warkworth will not be completed until 2019 and the final stage not until 2022.

Mr Reid said yesterday's congestion could have been eased if more drivers had taken the alternative State Highway 16 route to Wellsford. "The strange thing is people don't like using SH16 despite being encouraged to do so, and it's a nice scenic road if you're not in a hurry."

Although most drivers were well behaved, some were in a hurry to overtake everyone else in rare passing lanes, only to become stuck in queues as traffic merged.

"There were just a few people in a real hurry, which is disappointing because they just come across another queue and it's not like they're going to a doctor's appointment," Mr Reid said.

"Everyone is going on holiday - I can't see the point [of hurrying]."

Motorists driving to the Coromandel waited for more than an hour in a queue 4km to 5km long to cross the one-lane Kopu Bridge early yesterday afternoon.

The bridge's traffic lights were replaced by manual "stop-go" traffic signs, and the queue was whittled back to less than 1km by 4pm, said Constable Ian Cornelius of Thames.

A police officer was also on duty at the intersection of State Highway 25 and the Thames-Paeroa road to ensure a smooth flow of vehicles from the bridge towards the main Kopu-Hikuai route to the eastern Coromandel.

That difficult intersection and the dog-leg leading to it will be replaced in 2012 by a large roundabout leading directly to a new two-lane Kopu Bridge.

Although the bridge looks almost complete to queuing motorists, peaty soils beside the Waihou River require lengthy compacting work before approach roads can be finished.

The jams showed that many people were not letting the latest petrol rise, of 2c a litre, spoil their holidays.

Motorists are now paying 197.9c at most main-centre pumps, except for those buying from Gull's small group of service stations, where prices of 194.9c for the regular grade and 193.9c for biofuel will not be reviewed until tomorrow.

AA spokesman Mike Noon said although the rise seemed justified, "it still feels like strawberries going up before Christmas".