Mountain rescuers today warned of the dangers of leaving without a proper plan after seven climbers were stranded overnight on mountains in Mayo.
A hillwalker in his 40s lost his way in the fog on the Croaghaun Mountain in Achill last night, while a group of six students had to be rescued from the top of Mweelrea mountain 24 hours earlier.
The Mayo Mountain Rescue team said that although both the hillwalker and the students had adequate protection gear, they had not been prepared for the foggy conditions.
"The hills are great and we want people to enjoy them, but leave a note telling people where you're going and what route you're taking. You need to have an exit strategy - if the fog comes down suddenly, are you going to come down off the mountain or stay there?" said spokesman Shane McGuire.
Around 20 volunteers from the mountain rescue team were involved in both operations.
The hillwalker, who is from Knock, was reported missing last night when he failed to return to his bed and breakfast in Achill.
"We started at 6am and the search began at 7am. It was very foggy so we tasked the Coastguard helicopter and we came across him as he was walking down," said Mr McGuire.
The 668 metre-high Croaghaun Mountain is located at the western end of Achill Island, which boasts some of the highest sea cliffs in Europe.
The hillwalker was reported to be shaken by the experience but uninjured and was taken to a local GP for a check-up.
On Friday night, the three male and three female students from the Galway Mayo Institute of Technology (GMIT) in Castlebar became disorientated in the fog on the 760 meter high- Mweelrea mountain but managed to stay warm for the night in their bivouac bags.
They were located unharmed by the mountain rescue team yesterday morning and were able to walk down the mountain without assistance.
The students had raised the alarm when one of them rang his local garda in Tipperary, who then relayed the message to Gardai in Westport.
Mr McGuire said there was a danger that people were relying on their phones to get them out of trouble.
"The higher the hills, the better the coverage, so the calls will get through. But a phone is no substitute for navigation skills."
The Mayo Mountain Rescue team have been called out around 30 times so far this year, with most incidents occurring on Croagh Patrick, which is climbed by hundreds of people each week.