An avalanche is a large mass of rock debris or snow that moves rapidly down a mountain slope, sweeping everything in its path. There are three types of avalanches: dry snow avalanches move the fastest, wet snow avalanches move slower, and slab avalanches break off as slabs that split into pieces. Avalanches typically occur in mountainous areas with heavy snowfall between January and March, and can be triggered by vibrations, spring rains, or warm winds. While avalanches rarely damage towns due to occurring in remote high mountain areas, they can destroy forests and buildings in their path as well as claiming human lives, particularly skiers. Various prevention methods are used such as building snow fences