Police in Canterbury are fed up with drivers cutting corners.
Tickets were issued to 63 drivers in six hours for failing to keep left at Hundalee, south of Kaikoura.
Sergeant John Hamilton is disappointed by what he calls the blase attitude of some drivers.
One was charged with dangerous driving after overtaking a line of vehicles going into a blind bend.
Police say drivers who fail to keep left will be fined and face up to 20 demerit points.