The Department of Conservation has closed the Abel Tasman Coast Track north of Anchorage because of damage caused by heavy rain in the Nelson-Tasman region.
It says there is no road access to the Heaphy Track at the Golden Bay end on Thursday.
DoC says the Marahau-Anchorage section of the Abel Tasman Coast track remains open, but the remainder is closed due to slips and other damage.
It arranged for an Abel Tasman Sea Shuttle boat to evacuate about 50 trampers who wanted to leave on Thursday from coastal areas of Abel Tasman National park from as far north as Totaranui.
DoC area manager Martin Rodd says the evacuation of the track had been the "easy part", but department staff have been "scratching their heads" about what to do about the track.
He told Checkpoint a giant rockfall had left a granite cliff, making it difficult to form a track and workers would look at creating a path to by-pass the obstacle at the weekend.
The alternative track, he says, would only be suitable for experienced trampers.