But as more and more of us head off for Nepal's Annapurna circuit, the Pyrennees or the Moroccan Atlas, so these fragile mountain environments grow increasingly threatened. With the help of information from Tourism Concern, the Himalyan Mountain Code and our own trekking experts, we've compiled the following simple guidelines for minimising the impact of your trek. Water sources Never pollute water sources with waste, soapy water or any other non-biodegradeable material. Litter Carry out of the mountains everything you took in with you - that includes all waste. It's a good idea to remove product packaging before you set off.
Toilet paper Burn it - never leave it tucked under a stone or skewered on branch.
Trails Wherever possible, stick to the main trail. Carving new paths through the mountains is a highly damaging form of erosion. There is also a safety advantage to staying on the main trails where other trekkers are more likely to come across you if you run into trouble. Fuel Conserve fuel - not just your own but that of locals too. Never burn firewood for fun.