A 27-year-old Swiss woman has been found "cold, but otherwise well", after spending a night in bush near Picton.
Police said the tourist had gone on a day-walk up Essens Valley when she sent a text message to a friend in Christchurch asking for help about 5.30pm.
She told her friend she had walked to a dam and then on to the summit.
Calls to her cell phone went unanswered.
Police said the woman was lightly clad and not equipped for a night in the bush.