Introduction

Wherever are mountains, there are avalanches. Our technology tries to fight it, but we will never fully control it. It is called the white death. Even the smallest avalanche can kill. The large one is able to knock down huge trees or even whipe out a village. Snow avalanche is not the only type of avalanches. Sometimes mountain itself can move downhill carrying milions of tons of material, changing the landscape for ever. The most deadly of all are hot ash flows from volcanos. These are avalanches too.