Charities are being urged to find alternatives to the Three Peaks Challenge, in which supporters raise money by climbing the three highest mountains in Great Britain in 24 hours.
The call comes from the British Mountaineering Council (BMC), which says that tens of thousands of charity walkers each year are eroding paths and putting too much pressure on communities.
The BMC's appeal is echoed by the National Trust and national park authorities in Snowdonia and the Lake District, which say charities should consider alternatives such as the second highest mountain in each country.
The challenge involves the ascent of Ben Nevis in Scotland, Scafell Pike in the Lake District, England and Snowdon in Wales. Climbers usually do it on summer weekends, travelling between the mountains in cars and minibuses.
"You sometimes have a dozen vehicles charging up Wasdale (in the Lake District) at one o'clock in the morning," said Clare Bond, access and conservation officer for the BMC. "Local people are left with problems such as car parking and litter, while the charities do quite well out of it."
There are no reliable numbers for those doing the Three Peaks, but more than 28,000 people passed the foot of Scafell Pike in June 2000. Outside the Three Peaks season, the monthly figure is less than 5,000.
In a recent article in the BMC journal Summit, Richard Palmer, a property manager at the National Trust in the Lake District, says that the numbers are "colossal" and the mountain "simply can't take it".
Charities have co-operated in a code of practice which says there should be no more than 200 participants and they should not arrive in the Lake District between midnight and 5 am.
Medical charity Action Research has organised several Three Peaks challenges and is doing another in July. A spokesman said he understood the concerns and "would welcome discussions with relevant bodies to ensure the best standards are maintained".
Contact Clare Bond on 0870 010 4878 or visit www.thebmc.co.uk.