A man became stuck on a Welsh mountain because his electronic mapping device broke and he only had a map of Scotland with him.
He was on a night reconnaissance on the 3,262ft (994m) Glyder Fach in Snowdonia in preparation for a challenge walk.
Members of the Ogwen Valley mountain rescue team helped him to safety.
A spokesman warned against depending on electronic applications in the mountains.
"Basically he was depending on an electronic tracking system which he then dropped and the screen broke," said Chris Lloyd.
"He never had a paper map of Wales with him, only a map of Scotland, and he was totally dependent on using the electronic device to find his way, so when it broke he was stuck."
The man called rescuers and two members of the Ogwen Valley team walked up the mountain to find him.
"We've had a couple of similar incidents over the past 10 days," Mr Lloyd added.
"One group was taking part in a Welsh 3,000 ft peaks challenge and was again depending on GPS when their battery ran out and they were still on the mountain.
"That resulted in our team being called out at 11pm at night.
"People should have a paper map of the correct area, and by all means use the electronic equipment to check your co-ordinates, but don't depend on it because if you are out on the mountain for hours at a time batteries go flat," he added.