Bad weather and the risk of rockfalls has forced the closure of State Highway 1 south of Kaikoura.
The road, which was badly damaged in November's magnitude 7.8 earthquake, has been closed between Peketa and Goose Bay.
It was expected to be closed until tomorrow.
Motorists travelling to Kaikoura in the meantime have been advised to use Inland Route 70 between Culverden and Kaikoura.
The closure comes during the busy summer tourism season as the region works to rebuild after the quakes.