Police have recorded more than 600 drivers going over the speed limit in Dome Valley, a black spot north of Auckland.
The vehicles were photographed over six hours there on Sunday.
Inspector Mark Fergus said Dome Valley has one of the highest crash rates in the country, with many crashes related to speed.
Officers are issuing tickets to drivers spotted going any more than 4km per hour over the speed limit.
Traffic safety cameras are also set to issue tickets at that speed.