Massive ice towers, torrents of water, crevasses and blistering snowstorms bar their path, but the climbers force themselves onward, scaling vertical cliffs of compacted snow and ice to reach the top of the world.

With Snow, a documentary film by climber Namgyal Sherpa, shows the ordeals faced by mountaineers in their quest to climb the world's highest peak. The film has now been screened in nearly a dozen countries, including the US, Japan, Switzerland and India, and has sold more than 20,000 copies.

Namgyal, who has reached the summit of Chomolungma three times, is donating profits from the film to the families of those who have died in accidents on the mountain. The idea for the film came to him during one of his ascents, when he witnessed a fellow climber, an American, collapse due to lack of oxygen.

He also saw some of the many bodies that still lie on the summit ridge of Chomolungma, and decided he wanted to show the rest of the world how difficult it really is to climb the mountain.

Just like the climbing, the filming was no easy feat. The 40-minute documentary, shot last year, required a team of 19 people who, in addition to climbing the mountain itself, were required to follow the climbers with heavy filming equipment. Only nine of the 19, including Namgyal himself, reached the summit during the 65 days of filming.

The documentary, which cost Rs 1.5 million, follows a team of mountaineers all the way to the top. It shows the mountains as they look from above 7,000m, offering armchair viewers breath-taking sights they would never be able to see for themselves.

The hardships 30-year-old Namgyal faced while making the film were nothing new for him. His father, from Khotang, died when he was six years old and his mother ran off with another man. He was raised by relatives and came to Kathmandu after completing tenth grade.

He worked for a while as a porter and was later offered a job at Explore Himalaya, a trekking and climbing outfit. The company, impressed by his abilities, eventually gave him the chance to climb Chomolungma, and today he is a climbing guide at the company.

"The documentary gave me a chance to show the world how we climb mountains," Namgyal says. "This is a major accomplishment in my life."