Three trampers in north Canterbury had to be rescued after their path became blocked by knee-deep snow and ice, prompting police to warn day-trippers to know their limits.
Police say a woman and two friends became lost near the top of Mt Oxford on Saturday night.
"Knee-deep snow was preventing them from moving forward, the path behind them had turned to ice, and they were not sure of their exact location," they said in a statement.
"They were not prepared for the conditions and had very little equipment with them."
A rescue helicopter was able to locate them and rescue them, but police said it could have taken rescuers up to six hours to reach them on foot.
They've warned day walkers and trampers to plan their trips, take adequate supplies and know their limits.