State Highway 15
Also known as the Northland Inland Freight Route, State Highway 15 is one of New Zealand’s newest highways.
It runs concurrently with a stretch of SH1 between the Ruakākā roundabout before turning inland at Otaika Valley. It winds up Otaika Valley Road where it crosses SH14 at Maungatapere before travelling along Mangakahia Road to Kaihohe and on to Okaihau in the north.
Prior to 1930, the recommended route from Whangārei to Kaitaia was via Mangakahia because the Hikurangi Swamp north of Whangārei was virtually impassable. This inland route was named Highway 1.
However, when a better 'all weather' road was completed from Whangārei north, this became the new Highway 1.
Approximately 90 years later a formal designation for Mangakahia Road was re-instated as State Highway 15. In August 2016 NZTA Waka Kotahi took over management of the 96km stretch of roads which runs from the Port Marsden Highway to Okaihau.