South West Communications Group's Engineering Director Brian Lodge was saved by his ice axe during a fall on a charity climbing expedition to scale Mont Blanc.
"After hours of climbing in the dark with head torches we hit a new crevasse and ice wall at around 4,000m which had not been there previously," he said.
"We could not cross so had to turn around. I fell and performed a self arrest technique with my ice axe. The training clearly paid off.
"We ended up climbing along a rock ridge on the way back with a 3,500m drop on one side. I was genuinely scared to death."
Lodge was joined by his son Sam along with Greendale Farm Shop and Ladrum Bay Holiday Park owner Robin Carter and his daughter Joy for the expedition.
The plan to summit Mont Blanc was aborted when the mountain leaders deemed the conditions to be unsafe.
Attention then turned to Mnch, which is one of a group of three mountains including the Eiger and Jungfrau in the Alps, with its summit measuring 4,100 metres.
Lodge said: "Mnch was described to us as less plod and more technical. We needed to be confident in exposure at height as the summit was approached by a one foot wide ridge at over 4km high. We were roped to two mountain leaders just in case."
The climb aimed to raise finds for two local charities. The Exeter Foundation raises funds for a number of charities in the city while The C Group supports wounded Royal Marines. Lodge and his son Sam have raised £840 towards their £1,000 target.