Speed limits between Masterton and Featherston in Wairarapa are about to be reduced.
Waka Kotahi data shows there have been 488 crashes on this stretch of State Highway 2 between 2010 and 2019; four people were killed and 28 seriously injured.
From 27 January, the limit on open-road sections will come down from 100 to 80km/h.
Limits outside schools will drop to between 30 and 50km/h at the start and end of the school day.
Waka Kotahi director of regional relationships Emma Speight said that even when speed did not cause a crash, it was always a factor in the severity of injury.
Last year, Waka Kotahi opened its Interim Speed Management Plan to public consultation. The plan would reduce some 100km/h zones, such as the winding Remutaka Hill Road between Wellington and Wairarapa, to as low as 60km/h.
RNZ