Landslips on State Highway 1 on the Christchurch to Picton route via Kaikoura caused by former cyclone Gita have been cleared enough to allow the road to re-open.
The New Zealand Transport Agency says the road is open from this morning but drivers should expect delays as the road is down to one lane in more sections because of Gita.
The usual five-hour trip from Christchurch to Picton via Kaikoura is likely to take five-and-a-half hours and people should still consider using the alternative inland route through Lewis Pass.
The agency has previously said Gita brought down about 300,000 cubic metres of material at 60 sites both north and south of Kaikoura, from Parnassus on the south side, to Clarence on the north.
The biggest of these was just south of Okiwi Bay, at Jacob's Ladder, north of Kaikoura where 200,000cu m of material was dislodged by heavy rain.