Train passengers aiming to go on the Interislander ferry over the Cook Strait are unable to get to Picton because of a road closure.
State Highway 1 at Peketa, south of Kaikoura, is likely to be closed until at least Monday, after a major landslide.
An estimated 15,000 cubic metres of earth and rocks have fallen on to the road, about 15km from the town.
Kiwirail says the slip is blocking the railway line between Christchurch and Picton and that's forced the suspension of its passenger train service until further notice.
Kiwirail says a replacement bus service is not available, meaning it cannot transport people to the Interislander ferry to Wellington.
General manager Deborah Hume says this is because the only alternative route for coaches and other heavy vehicles - via State Highway 63 in the Wairau Valley and State Highway 7 at Lewis Pass - would almost double the journey time.
Cars are being diverted on to the Inland Kaikoura Road, though police warn this route could add hours to a journey between Picton and Christchurch.
Inspector Warren Kemp says the slip has been attributed to heavy rain, not earthquake activity.
