What regions have the most elevated car crash risk these holidays?

The message of the map is clear - all roads in New Zealand have the potential for tragedy.

Using data from the New Zealand Transport Agency, the Herald has calculated what regions have the most elevated risk of a crash over the holiday period by marking the location of every Christmas and New Year car crash over the last 16 years.

The markings produced an almost-complete outline of New Zealand.

The holiday period this year started at 4pm Friday and ends 6am on January 4. The period has varied over the years but is between nine and 12 days.

Seven people have died on our roads so far, following a double-fatal crash in Waimate yesterday. Nineteen died during the last holiday period.

The 10 districts where the risk during the holiday period is most elevated are, in order: Thames-Coromandel (311 crashes), Far North (457), Tauranga (482), Taupo (292), Queenstown-Lake district (269), Gisborne (298), Waikato (354), Tasman (250), Whangarei (365), and Hauraki (189).

Herald data journalist Chris Knox took the total number of crashes during the Christmas period and divided it by the total number of crashes during the rest of the year and then weighted this number by the number of Christmas period crashes to calculate a risk factor.

The risks in major cities like Auckland and Wellington were low risk as motorists tended to flock to beach towns for the summer.

"In these holiday destinations, people need to expect more traffic and expect more risk," said NZTA's safety and environment director Harry Wilson.

"The biggest differences are made by putting on a seatbelt and slowing down. The slower you go the less the mess."

Another message from the NZTA's examination of the data is that the factors affecting crashes during the Christmas holiday period are essentially the same as during the rest of the year.

"There is a perception that the holiday road tool is fuelled by bad driving - but it is not." Wilson said.

"There is nothing unusual about Christmas. The underlying causes of crashes are the same as during the rest of the year. The higher volume of traffic simply increases the risk.

"The headline statistic is that 50 per cent of fatal and serious crashes are simply ordinary drivers making a mistake. NZTA is looking to put in place the measures to try and make the difference between death and survival. But a reduction in vehicle speeds is one of the most significant ways to improve survival."

He said that people's perception of time saved by going faster "is almost always wrong".

"Travelling 10km at 110 km/h instead of 100 km/h saves, at most, 30 seconds."

Police are also emphasising the need to reduce speed.

In the launch of their "We Want You Here for Christmas" campaign, they state that reduced speed tolerances will be in place for the holiday period.

From December 18 to January 8, if motorists are detected by a speed camera exceeding the area's posted speed limit by more than 4km, they are likely to be ticketed.

"Police focus is on ensuring people are driving safely and to the conditions and a threshold is one of the many options police use to ensure this," a police spokesperson said.

In 2016, speed was a contributing factor in 81 fatal crashes, 418 serious injury crashes and 1258 minor injury crashes.

The Automobile Association spokeswoman Mehpara Khan added: "The AA supports the police's enforcement of lower speeding thresholds during holiday periods. However, the AA also advocates that the enforcement be targeted to high risk roads."