Winter is cold, dreary, and miserable for many of us, but for those who love to ski, winter is the best time of the year.

If you've ever raced down a mountain on skis or snowboards, you know that it's a thrilling experience that is usually coupled with fantastic views. It's why so many people around the world travel to far off locations just to propel themselves down mountains.

The Swiss Alps provide some of the best skiing in the world and millions of tourists visit them every year. However, any accomplished skier knows that there are dangers associated with the popular sport.

While some risks are obvious, like crashing, frostbite and even sunburns, there is another, more frightening, pitfall for those who frequent mountains during the winter: avalanches.

An avalanche is caused when snow shifts and almost anything may trigger them. They're not particularly rare, but they can be devastating if they hit a populated area.

Alexis Ramu is an avid skier who recently visited the Swiss Alps. He uploaded a shocking video to Twitter that has since been viewed thousands of times. It's clear that Ramu is lucky to be alive.

The avalanche, which struck the popular Crans-Montana resort, cascades down the mountain shortly after Ramu's video begins. He races ahead of it, but frequently turns back.

You can see the wall of snow devour two skiers behind him.

It's heart-stopping, first-hand footage of an avalanche. Thankfully Ramu was unhurt in the filming, but the avalanche did have a deadly result.

One person died in hospital after being swept up in the slide. Three others were hurt but are expected to recover.

Usually ski slopes avoid avalanches as snow levels and conditions are carefully monitored. The 34-year-old man who was killed was reportedly part of Crans-Montana's ski patrol service.

An investigation is underway.