The men got stuck after taking a short cut to Snowdon's summit. Photo: Chris March CC-BY-SA-2.0

A rescue helicopter called to an exhausted walker on Wales’s highest mountain had to be diverted to pluck three ill-prepared men who had got stuck on dangerous ground after taking a short-cut.

The trio, in their 20s and from north-west England, were taking part in a sponsored event on Snowdon yesterday.

They were part of a group of more than 40 tackling the walk from Pen y Pass to the mountain’s 1,085m (3,560ft) summit via the Pyg Track.

John Grisdale, of Llanberis Mountain Rescue Team, which was alerted to the group at 3.30pm, said the trio became cragfast on Trinity Gully. “The party wished to reach the summit ahead of the main group and decided to ascend the gully which exits on the summit cairn rather than follow the normal path.

“This is a 300m-long gully which is often ascended in winter by experienced mountaineers when the gully is full of snow and ice and requires the use of specialist equipment.

“In summer, however, its steep grassy slopes, loose rocks and scree make it a hazardous location.

“Never having visited the mountain previously, with no technical climbing equipment or adequate clothing or footwear the three placed themselves in a very precarious position and became cragfast high in the gulley.

“A slip by one or all would probably have serious consequences.”

An RAF Sea King had to divert from its rescue of an exhausted woman

The team was already on the mountain after being called to help the woman who was suffering from exhaustion. A Sea King helicopter from RAF Valley was also taking part in the rescue.

Mr Grisdale said: “This had to be delayed because of the seriousness of the apparent danger to the three.”

The Llanberis team said organisers of sponsored events should make sure participants were correctly briefed and equipped.

Mr Grisdale said: “May to September is the favoured time for sponsored events to the summit of Snowdon.

“It is a daily occurrence to see large groups attempting the challenge. However, it seems these three were let loose on the mountain without prior directions, no apparent leader or controller for the group.

“The mountains deserve to be respected and planning for such events needs to be meticulous.

“Organisers of charity events have a responsibility for the safety of their participants. There was no apparent method of accounting for the group’s safety whilst on the mountain.

“Even though the weather was sunny, dry and not a cloud in the sky the wind was cold especially in the shadows of the Trinity Gully. Their ‘city’ clothes and lightweight trainers were totally unsuitable for their challenge.

“Their complete inexperience of the mountain environment and their lack of appreciation of the dangers involved in their chosen route might have benefited from some prior walk or training on lower and safer hills.

“Having become cragfast in the gully the group was fortuitous in that other walkers saw their predicament and were able to raise the alarm. Mobile phone signal is not available in many locations on the mountains.

“The rescue helicopter was attending to another incident on a lower path and had to be diverted to winch these three who were deemed to be in a very precarious location.

“They delayed the arrival of another person in hospital.”

He added that many charity events provide excellent guidance and support for their walkers and the Snowdonia National Park Authority has guidance notes for sponsored event organisers.